UNITED STATES SECURITIES AND EXCHANGE COMMISSION

FORM 10-K

For the fiscal year ended December 31, 2004

For the transition period from __________ to __________

Commission file Number: 1-16239

ATMI, Inc.

203-794-1100

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

Common Stock, $.01 par value

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K o

Indicate by check mark whether the registrant is an accelerated filer (as defined by Rule 12b-2 of the Act). Yes þ No o

The aggregate market value of the voting stock held by non-affiliates of the registrant at June 30, 2004, was approximately $850,241,411 based on the closing price of $27.31 per share.

The number of shares outstanding of the registrant’s common stock as of March 9, 2005 was 32,278,580

DOCUMENTS INCORPORATED BY REFERENCE:

Proxy statement for the annual meeting of stockholders to be held on May 24, 2005 (Part III).

ATMI, INC.
Annual Report on Form 10-K
For the Fiscal Year Ended December 31, 2004

TABLE OF CONTENTS

PART I

     References in this annual report to the “Company,” “ATMI,” “we,” “us” and “our” refer to ATMI, Inc. and our wholly-owned subsidiaries on a consolidated basis, unless otherwise stated.

Item 1. Business

     ATMI is a leading supplier of materials, materials delivery systems and high-purity materials packaging products used worldwide in the manufacture of semiconductor devices. ATMI specifically targets the “front-end” semiconductor materials market. This market includes the processes used to convert a bare silicon wafer into a fully functional wafer that contains many copies of a semiconductor device or “chip.” To complete the manufacturing process, this functional wafer is taken through a “back-end” manufacturing process that includes wafer dicing into chips, packaging and testing. ATMI’s customers include many of the leading semiconductor manufacturers in the world. ATMI has further refined its market focus to target specialty materials used in front-end semiconductor manufacturing. These specialty materials are applied in eight key process steps that are used repetitively to add functionality to a silicon wafer.

     The semiconductor industry has grown worldwide over time and front-end manufacturing processes have become increasingly complex, resulting in rapidly changing requirements for semiconductor materials. ATMI has capitalized on the growth of the semiconductor industry in general, and front-end processing in particular, through:

	•	a comprehensive research and development program that has provided a stream of proprietary and patented products for this market;
	•	customer focused applications development to provide material solutions at future technology nodes;
	•	a strategy of providing a comprehensive array of semiconductor materials products (ATMI now offers materials consumed in five of the eight front-end processes used in semiconductor manufacturing); and
	•	a targeted acquisition effort that has allowed us to move toward a complete product portfolio more rapidly.

     During 2004, ATMI significantly reduced its exposure to the capital equipment cycles of the semiconductor industry by selling non-core product lines (which represented nearly all of our former Technologies segment). The non-core product lines that we exited by sale included the following: environmental abatement equipment, materials sensing and monitoring equipment, specialty thin-film deposition services, outsourced parts cleaning and tool maintenance services, a smartcard device venture and gallium nitride materials.

     ATMI’s continuing operations comprise one reportable business segment.

     ATMI provides:

	•	a broad range of ultrahigh-purity semiconductor materials and materials delivery systems; and
	•	ultra-high purity materials packaging with applications in the semiconductor and pharmaceutical industries.

     ATMI’s business consists of consumables that generally track wafer starts, or the approximate square inches of silicon wafers processed into fully functional semiconductor devices. Additional financial information about the Company and related geographic information can be found in the “Management’s Discussion and Analysis of Financial Condition and Results of Operations” section of this Form 10-K.

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     ATMI has achieved a leadership position in high-purity materials, materials delivery systems and high-purity semiconductor packaging products by providing a more complete line of products than its competitors through innovation and acquisitions. ATMI’s focus has been on providing material solutions to our customers that will allow them to make faster, better and more reliable chips. We also focus on working with customers to bring new materials processes into ramped production as quickly and efficiently as possible. ATMI plans to continue its growth through product line expansion and to leverage its core technology to create new high growth product lines, including growing its leadership position in copper advanced interconnect markets.

Semiconductor Industry Background

     The demand for semiconductor devices has grown significantly over time as the use of semiconductor devices has proliferated in a wide variety of consumer and industrial products, especially in computing, networking and communications equipment. This increase in demand for semiconductor devices has been fueled by the ability of semiconductor manufacturers to deliver products with:

	•	consistently enhanced performance characteristics and functionality;
	•	improved reliability;
	•	increased memory capacity;
	•	reduced size, weight, power consumption and cost.

These advances have been made possible by innovations in the fabrication processes and in the materials and delivery systems used in manufacturing advanced semiconductor devices. At the same time, as the construction and management of fabrication facilities has become more complex, semiconductor manufacturers continually seek to streamline their supplier relationships and reduce the number of suppliers upon which they rely. Because of this trend, consolidation among the providers of semiconductor materials and materials delivery systems is expected to continue.

Semiconductor Manufacturing Process

     Semiconductor devices are manufactured by repeating a complex series of process steps on a wafer substrate usually made of silicon. The primary process steps include various kinds of materials deposition (physical vapor deposition, chemical vapor deposition, electrochemical deposition and ion implantation), etch, wafer preparation (chemical mechanical planarization), patterning (photolithography) and cleaning (photoresist stripping), each of which is described in more detail below.

     The industry is currently being revolutionalized by a transformation from aluminum wiring to copper wiring in advanced semiconductor chips. Copper wiring requires many new materials to be developed, such as barriers and insulators, pre- and post- deposition cleaners, pre- and post-chemical mechanical planarization (“CMP”) cleaners, and post-etch photoresist and post-strip residue removers. Each new layer of copper generates a need for several additional materials.

     During deposition processes, several layers of conducting, semi-conducting or insulating thin films are formed on a wafer. Precise and reliable control of the deposition of these films is vital to the ultimate performance of an individual device.

     The most mature processes for thin film deposition and modification are physical vapor deposition, also known as PVD or sputtering, and ion implantation. In PVD, which is used primarily for the deposition of conducting metal layers, a high energy beam is directed at a high purity metal target which in turn causes the displacement of metal atoms that are showered over the wafer, coating it with a thin metallic film. Ion implantation is a gas-based process

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used principally to modify (or dope) semi-conducting layers with a high-energy beam of material that is “implanted” into an existing thin film.

     Chemical vapor deposition, or CVD, is a process used in the deposition of semi-conducting and insulating thin films. In the CVD process, wafers are placed in a sophisticated reaction chamber and a specially designed gas or vaporized liquid material is introduced. Simultaneously, a form of energy, such as heat or plasma, is added to the reactor to cause the decomposition of the material being introduced. As a result of this decomposition, a thin film of material is deposited on the surface of the wafer. CVD based processes have certain advantages over PVD based processes, including:

	•	the relative thinness of the films applied to the wafer;
	•	conformality (ability to coat evenly, especially in holes and trenches designed into the device);
	•	purity; and
	•	the ability to coat large areas.

These advantages have led to rapid growth in sales of reactors and related CVD process consumables and equipment. Consumables and related equipment include the raw materials used in the CVD process and the delivery systems required to transport the materials around a semiconductor plant and to a reactor.

     Electrochemical deposition, or ECD, is growing rapidly as a result of the industry’s desire to use copper as the conducting layer in certain devices. The use of copper allows for smaller circuits, because copper greatly reduces power consumption while increasing integrated circuit (IC) speed. Nature favors copper over aluminum wiring because of its higher conductivity and greater resistance to thermally and electrically induced short circuits. In ECD, the wafer is submerged in a bath of copper electroplating solution which, when appropriately charged, deposits a thin film of copper on the wafer.

     Etch is a process that selectively erodes away certain thin film materials. It is carried out either “dry” with corrosive gases or “wet” with energized liquids. As semiconductor manufacturing facilities (or “fabs”) migrate to copper wiring as the main component inside advanced integrated circuits, new advanced interconnect materials are required.

     CMP is used to prepare a wafer for patterning photolithography. As wafers are processed, thin film thicknesses inevitably vary across the surface of the wafer. Due to the fine line widths used in photolithography, present-day wafers need to be perfectly flat. CMP flattens the processed wafer by polishing the wafer using a mechanical polishing pad and a slurry, which is an abrasive solution containing solid materials and chemicals which selectively erodes away the appropriate excess materials. Given the migration to copper, precision surface preparation and cleaning materials become more critical in the fabrication of advanced interconnect devices.

     Photolithography is the process whereby patterns are developed on the wafer surface. The process is begun by spinning a photosensitive material called “photoresist” or “resist” onto the wafer surface and shining light through a patterned photomask to selectively harden the resist. Photoresist strip is the process of stripping or otherwise removing excess resist material and allowing for the fabrication of the wafer’s circuitry.

     Because thin film materials are consumables, the market for these materials and delivery systems generally tracks wafer starts. The thin film materials market is also segmented into a wide variety of material types and forms. For example, many thin film precursors are now sold as pressurized gases, which allows for easy transport around a typical semiconductor manufacturing plant. However, many of these gases are toxic and/or hazardous, leading to the development of safer alternatives including the use of liquid or solid materials and the adoption of gas handling technologies and delivery systems that minimize the danger of a catastrophic release of toxic gas.

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     In addition, semiconductor materials have exceptional purity requirements due to the extremely low tolerances for impurities and particulates in semiconductor processing. Liquids and solids used in making devices require special packaging to minimize exposure to air, airborne contamination and particulates.

     The market for semiconductor thin film materials has expanded and contracted with the growth and contractions of the market for semiconductor devices. The design of new thin film materials and delivery systems to transport these materials around a semiconductor plant has experienced ongoing innovation. This innovation has been driven by the demand for expanding semiconductor device capabilities and corresponding decreases in circuit dimensions.

ATMI’s Strategy

     ATMI’s objective is to establish and enhance leadership positions in each market it serves. ATMI’s strategy consists of the following key elements:

	•	Focus product development and application engineering initiatives with leading semiconductor manufacturers to provide advanced interconnect and next generation material solutions.
	•	Target high-growth, high-margin specialty markets that use ATMI’s core materials technologies and require products that are consumed in the production process.
	•	Add value through advanced high-purity packaging and dispensing systems designed to meet the demands of users for greater levels of purity, productivity, safety and environmental responsiveness.
	•	Leverage ATMI’s technology leadership by investing extensively in developing proprietary and patented materials and materials handling technology that the Company uses to commercialize new products and new solutions that will be required for future technology nodes.
	•	Form strategic alliances, including joint development programs and collaborative marketing efforts, to accelerate the introduction of ATMI’s products into markets that ATMI does not currently serve.

In summary, ATMI’s strategy does not envision a “traditional” materials supplier-to-customer relationship. In those relationships, suppliers tend to provide materials to customers based solely on the cost, quantity and quality of the materials being supplied. Instead, ATMI has worked to develop partnerships with its customers based on ATMI’s ability to improve the efficiency of customers’ manufacturing and supply chain processes, thereby lowering the integrated costs of materials to our customers.

Businesses and Products

     ATMI believes it is one of the fastest growing, and among the most innovative, suppliers of ultra-high purity semiconductor materials, materials delivery systems and ultra-high purity materials packaging to the semiconductor industry. ATMI has sought to take advantage of the changes in the market for materials, delivery systems and packaging by:

	•	developing and commercializing a broad range of “front-end” semiconductor materials;
	•	developing and commercializing low-pressure gas delivery systems for safe handling and delivery of toxic and hazardous gases to semiconductor process equipment;
	•	developing and commercializing innovative high-purity packaging systems that allow for the introduction of low volatility liquids and solids to semiconductor processes; and
	•	developing manufacturing processes to meet the critical purity and integrity requirements of the semiconductor industry.

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     In meeting the needs of its customers, which include semiconductor device manufacturers, chemical suppliers and semiconductor original equipment manufacturers, or OEMs, located throughout the world, and anticipating their future requirements, ATMI seeks to:

	•	offer the most complete line of consumable and delivery and packaging system products;
	•	offer the highest purity materials available;
	•	provide a high level of customer service and applications support;
	•	meet customer needs for statistical quality and process control and dock-to-stock programs; and
	•	meet the industry’s needs for advanced materials required for future generation devices.

     Products and Services. ATMI has three primary product lines: gas delivery systems, liquid materials and delivery systems and advanced high-purity packaging and delivery systems. ATMI also provides applications and analytical support services relating to each of these product lines.

Gas Delivery Systems

     Gas Delivery Systems ATMI’s patented SDS^® (the SDS^® product line or Safe Delivery Source) product line uses a standard gas cylinder containing an adsorbent material. The cylinder is filled with gas under conditions such that the gas is adsorbed onto the adsorbent material at sub-atmospheric pressure. Sub-atmospheric storage of hazardous gases minimizes potential leaks of gas during transportation and use, thus providing significant safety and environmental improvements over the traditional high-pressure cylinders. In addition, SDS^® products allow more gas to be stored in the cylinder, providing significantly higher rates of productivity than traditional methods of gas delivery used in ion implantation manufacturing processes. Since ion implantation processes operate at reduced pressures, the gas can be desorbed or released from the SDS^® gas sources using the ion implanter’s vacuum pumps. SDS^® gas sources can be installed and operated like conventional high-pressure gas cylinders with minimal maintenance. These advantages have led major chip manufacturers to adopt this technology as the industrial standard for dopant gas delivery.

     ATMI is a market leader in materials used in ion implantation applications with its SDS^® brand of implant gases. SDS^® materials include primarily arsine, phosphine and boron trifluoride. These products are manufactured by ATMI and ATMI’s exclusive distributor, Matheson Tri-Gas, Inc. In its continuous effort to improve SDS^® technology, ATMI recently introduced the third generation of SDS^® products, called the SDS3^™ product line The new product, while still maintaining all the inherent safety features of previous generation SDS^® products, dramatically increases the gas storage capacity by using newly invented adsorbent. The 2 to 3 times capacity improvement over existing products allows implanter users to further reduce tool down time, resulting in significant cost savings. ATMI has also successfully adopted the carbon adsorption technology and introduced new products for semiconductor deposition processes marketed under the SAGE^® brand. These applications include: low-k plasma-enhanced deposition, or “PE-CVD”, processes using low-k materials, pre-metal dielectric high-density plasma, or “HDP-CVD”, films utilizing phosphine gases and thermal deposition processes using germane gases. ATMI has also introduced a silane product used in processes such as HDP-CVD packaged in a novel vacuum-actuated cylinder (“VAC^®) for improved safety.

Liquid Materials and Delivery Systems

     Surface Preparation. ATMI’s AP™ and ST™ brand wafer photoresist strip cleaning materials are proprietary chemistries used for applications such as semiconductor post-etch residue removal, wafer etching, organics removal, negative resist removal, edge bead removal and corrosion prevention. The ST-250™ material is recognized as a leading material for the high-growth copper device post-etch residue removal application. This proprietary material is used for copper interconnects in advanced wafer fabs. Copper wiring in semiconductor devices is a rapid-growth

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segment with most major logic segment semiconductor companies in production at 130 nanometers. Our surface preparation products, acquired in connection with the acquisition of ESC, Inc., are being used in the most advanced copper fabs around the world for various surface preparation applications such as post-CMP cleaning and pre-nitride deposition surface treatment. ATMI expects that applications for these products will expand rapidly as the advanced IC device designs drop below 90 nanometers. The surface preparation technology has applications in IC as well as other niches such as LCD (liquid crystal display), disk drive and other areas.

     Copper Plating. ATMI is a market leader in materials used in copper electrochemical deposition applications with its Viaform^® brand of copper materials. ATMI purchased an exclusive, worldwide license to market and distribute Viaform^® materials in 2003 from Enthone, Inc., a subsidiary of Cookson Electronics. Viaform^® materials include inorganic and proprietary organic molecules that enable process efficiency in dual damascene copper processing applications. Dual damascene copper processing in semiconductor devices is a rapidly growing market with most major logic segment semiconductor companies in production at 130 and 90 nanometers with ongoing research and development in 65 and 45 nanometer technology nodes.

     Deposition. ATMI is also a leader in CVD products used for thin films in semiconductor manufacturing. ATMI markets these materials under the “UltraPur™” brand for pre-metal dielectric, dielectric and barrier applications. ATMI believes it is well positioned as the industry prepares to move to low-k dielectric films with the introduction of several new products in this area including “UltraPur™ OMCTS” (octamethylcyclotetrasiloxane), “UltraPur™ 4MS” (tetramethylsilane), “Super Dry™ TMCTS” (tetramethylcyclotetrasiloxane) and other materials. The low-k dielectric application is one of the fastest growing applications for dielectric deposition and is expected to become a mainstream technology at 90 and 65 nanometer device generations. ATMI is also well positioned for the incorporation of atomic layer deposition (ALD) processes by the semiconductor industry with its “ProE-Vap^TM” ampoule. This proprietary container allows for reliable delivery of low volatility solid precursors required for ALD.

     ATMI manufactures and markets chemical delivery systems under the Bulkfill™, Unichem™, 3Chem™ and RPM™ brands. ATMI’s patented canister technology and proprietary piping manifold purge technology make these systems a preferred solution, which reliably and safely manage materials in semiconductor fabs. These systems are designed to enable process tool efficiency through continuous refill of deposition tools, alleviating the need for costly tool shutdowns for container changes. The Bulkfill™ system is used for fab-wide distribution of TEOS (tetraethylorthosilicate), greatly reducing the frequency of container changes with its large 200-liter reservoirs. The 3Chem™ system is designed for BPSG (boron phosphorous silica glass) applications, combining the delivery of the boron, phosphorous and silicon precursors. The reduced pressure manifold or RPM™ gas delivery cabinet is designed to deliver ATMI’s proprietary sub-atmospheric SAGE^®and VAC^®gases.

     Chemical Mechanical Planarization. ATMI’s CMP products include the PlanarChem™ brand of materials. ATMI supplies materials for silicon oxide based film polishing for many different applications. ATMI is also developing copper and barrier polishing materials for the application of polishing copper-based dual damascene structures. These products are sold under the CERULEAN^® brand name and provide advantages to customers for simplicity and cost of ownership that provide lower defect rates while achieving high removal rates, thus providing overall process efficiency that is consistent with our core strategy.

Advanced High-Purity Packaging and Delivery Systems

     ATMI manufactures three different types of NOWPak^® container assemblies for packaging and delivery of ultra-high purity liquids: Bag-in-a-Bottle™ container system ; Bag-in-a-Can™ container system and Bag-in-a-Drum™ container system, each with its own companion dispense connection system. Each features a pre-cleaned collapsible inner liner, or “bag”, inside a rugged, high-density polyethylene or stainless steel overpack. The standard liner films are made of polytetrafluoroethylene, or proprietary multi-ply films of polyolefin and other polymers, which allow chemicals to be delivered to the manufacturing process without compromising their inherent purity. The empty inner liner is easily removed for waste consolidation, and the outer shell is recyclable or returnable for insertion of a new replacement liner. The dispense system promotes full utilization of the chemical, chemical isolation from environmental contamination and improved safety during dispense by sealing and isolating the

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chemical from the environment to protect further the chemical and the operator. It also ensures that the correct chemical is installed on the process through a key coding or RFID system.

     The largest current market for NOWPak^® packaging is photoresist and related chemicals used to pattern integrated circuits and flat panel displays. For integrated circuit patterning, these materials are typically packaged in Bag-in-a-Bottle™ containers that range in size from 1 to 10 liters. For flat panel display applications, larger 18-20 liter Bag-in-a-Bottle™ or Bag-in-a-Can™ containers are used. Recently, applications have expanded beyond photolithography chemicals in the semiconductor market to include ancillary chemicals, CMP slurries and process chemicals using the recently developed 200 liter Bag-in-a-Drum™ container system.

     ATMI also produces packages for high-purity solids under the Newform™ brand name. The Company makes high-purity flexible Ultra Clean packaging for the semiconductor and pharmaceutical industries. With its Newform™ products, ATMI packages critical materials and components for the semiconductor industry such as sputtering targets, wafer and disc shippers and cleanroom components. With the NOWPak^® liquid packaging system and Newform™ solids packaging, ATMI is addressing an increasing number of critical packaging needs for the microelectronics and pharmaceutical markets. Other markets for the Company’s proprietary high-purity packaging and delivery systems include the biotech and laboratory markets.

Customers, Sales and Marketing

     ATMI sells and distributes its products worldwide primarily through a direct global sales and service organization. For a breakdown of revenue by geography, see Note 17 to our consolidated financial statements. ATMI markets and sells its materials products to end-use customers, chemical suppliers and equipment suppliers through its direct sales force in North America, Europe, Taiwan, Korea, Japan, China and Singapore, with limited use of regional manufacturing representatives in certain parts of Asia. Additionally, ATMI’s materials delivery systems product lines are marketed and sold to semiconductor equipment OEMs, who in turn resell to end-users. NOWPak^® containers are generally sold to chemical suppliers, who sell their high purity chemicals in NOWPak^® containers at the request of end-users. Newform™ packaging products are sold directly to semiconductor and pharmaceutical companies, predominately in Europe and to an increasing extent in the United States. ATMI sells its SDS^® products for ion implant applications directly to certain end-users and through an exclusive distribution agreement with Matheson Tri-Gas.

     The majority of ATMI’s sales are to customers in the worldwide semiconductor industry. Results of operations, therefore, are materially dependent upon economic and business conditions in the semiconductor industry. The semiconductor industry is highly cyclical and while it has historically experienced significant growth, periods of reduced semiconductor unit demand and manufacturing overcapacity have resulted and could result again in significantly reduced demand for semiconductor materials, including the materials, materials delivery systems and ultra-high purity packaging products sold by ATMI.

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Manufacturing

     The following table summarizes the locations, products manufactured and size of ATMI’s various manufacturing facilities as of December 31, 2004.

Competition

     ATMI’s primary competitors in the semiconductor materials product lines are the Schumacher and Ashland divisions of Air Products and Chemicals, Inc., the EKC Division of DuPont and the Shipley division of Rohm and Haas. There are several additional companies outside the United States that compete with ATMI.

     ATMI’s SDS^® brand product currently has no widely established direct competition. Several companies compete with high-pressure gas cylinders and solid sources. There are numerous domestic and foreign companies that offer products that compete with ATMI’s high-purity materials, materials delivery systems and ultra-high purity packaging and chemical dispensing system products. ATMI believes that its ability to compete in the markets for containers and dispensing systems is dependent largely upon its patented NOWPak^® technology and its proven ability to enhance and improve its products and technologies. Increased competition has and may continue to impact the prices we are able to charge for our products. In addition, our competitors could have or obtain intellectual property rights which could restrict our ability to market our existing products and / or to innovate and develop new products.

Research and Development

     The Company’s research and development expenses consist of personnel and other direct and indirect costs for internally funded project development. ATMI also participates in joint development efforts with certain semiconductor manufacturers and semiconductor equipment OEMs. Total expenses for research and development for the years ended December 31, 2004, 2003 and 2002 were $19.6 million, $19.2 million and $13.8 million, respectively, including amounts reimbursed by external parties through contract funding and cost share agreements of $0.7 million, $0.8 million and $1.6 million in 2004, 2003 and 2002, respectively. Total research and development expenditures represented 7.9%, 11.2% and 10.1% of revenues in 2004, 2003 and 2002, respectively.

Strategic Alliances

     ATMI forms strategic alliances, including joint development programs and collaborative marketing efforts, to accelerate the introduction of its products into markets that have manufacturing or distribution barriers. These

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programs have led to significant technological advances, including the development of proprietary advanced materials and semiconductor manufacturing processes. ATMI has entered into an exclusive license, manufacture and distribution agreement with Matheson Gas Products, Inc. (“Matheson”), whereby ATMI has granted licensing rights for the manufacturing and worldwide distribution of certain SDS^â products to Matheson. Both ATMI and Matheson manufacture SDS^â products for worldwide distribution under this exclusive agreement. ATMI has also entered into a strategic alliance with Enthone, Inc., a Cookson Electronics Company (“Enthone”), whereby ATMI purchased the exclusive worldwide selling and distribution rights to Enthone’s copper electrochemical deposition (ECD) products, including its ViaForm^â products, for a period of ten years, subject to automatic renewal upon satisfaction of certain conditions. Under the terms of the agreement, Enthone continues to manufacture the ViaForm^â products for ATMI. Most of ATMI’s other strategic alliances are with leading semiconductor manufacturers or OEMs, each of which has participated with the Company in advanced materials and process development programs. These programs enhance ATMI’s core technology base and promote the introduction of targeted products.

Backlog

     ATMI does not track backlog, since substantial portions of the business are conducted with open-ended, supply contracts that do not specify quantities. Also, the SDS^â gas delivery source product, marketed principally through Matheson as an exclusive distributor for the ion implant market, carries no backlog. Therefore, the Company does not believe that backlog as of any particular date is indicative of future results.

Patents and Proprietary Rights

     ATMI has made a significant investment in securing intellectual property protection for its technology and products. ATMI seeks to protect its technology by, among other things, filing patent applications where appropriate. The Company also relies upon trade secrets, unpatented know-how, continuing technological innovation and licensing opportunities to help develop and maintain its competitive position.

     As of February 15, 2005, ATMI owns or controls approximately 284 United States patents and had approximately 116 current United States patent applications pending. Foreign counterparts of certain of these applications have been filed, or may be filed at an appropriate time. ATMI decides on a case-by-case basis whether, and in what countries, it will file counterparts of a United States patent application outside the United States. ATMI’s United States patents expire between approximately 2005 and 2024. ATMI also holds approximately 23 United States registered trademarks.

     ATMI’s ability to compete effectively with other companies will depend, in part, on its ability to maintain the proprietary nature of its technology. Although the Company has been awarded, has filed applications for, or has been licensed under numerous patents in the United States and other countries, there can be no assurance concerning the degree of protection afforded by these patents or the likelihood that pending patents will be issued.

     ATMI requires all employees and most consultants, outside scientific collaborators, sponsored researchers and other advisors to execute confidentiality agreements upon the commencement of employment or consulting relationships with the Company. These agreements provide that all confidential information developed or made known to the entity or individual during the course of the entity’s or individual’s relationship with ATMI is to be kept confidential and not disclosed to third parties except in specific circumstances. All of ATMI’s employees have entered into agreements providing for the assignment of rights to inventions made by them while employed by the Company.

Environmental Regulation

     ATMI uses hazardous materials and generates regulated waste streams as part of its manufacturing, processing and R&D activities. As a result, the Company is subject to a variety of governmental regulations related to the storage, use and disposal of these materials. ATMI’s failure to comply with present or future laws could result in fines or other liabilities being imposed on the Company, suspension of production or a cessation of operations.

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     The various premises that ATMI occupies may have been contaminated prior to occupancy. ATMI is not aware of any material environmental investigation or action by government agencies involving these premises. However, under federal and state statutes and regulations, a government agency may seek to recover its response costs or require future remedial measures from both operators and owners of property where releases of hazardous substances have occurred or are ongoing. The Company has secured indemnifications for remediation costs in connection with certain potential pre-existing, on-site contamination or environmental conditions. However, these indemnifications may not prove adequate to cover any liability imposed on the Company related to the environmental condition of the premises or the cost of defending an environmental action, either of which could be substantial.

     ATMI’s activities may also result in the Company being subject to additional regulation. Such regulations could require ATMI to acquire significant additional equipment or to incur other substantial expenses to comply with environmental laws. ATMI’s failure to control properly the use of hazardous substances could subject the Company to substantial liabilities.

Employees

     As of December 31, 2004, ATMI employed 671 individuals, including 302 in sales, marketing and administration, 262 in operations and 107 in research and development. Of these employees, 37 hold Ph.D. degrees and 67 hold other advanced degrees in electrical engineering, materials science, chemistry, physics or other technical fields. Only 5% of the Company’s employees are covered by a collective bargaining agreement, which expired in December 2004. ATMI is currently in the process of negotiating a new collective bargaining agreement with agents of this employee group and expects to have this accomplished by the second quarter of 2005. All of the employees covered by this agreement are based in Europe. ATMI has never experienced any work stoppages and considers its relations with its employees to be good.

Company Information

     ATMI was incorporated under the laws of Delaware in 1997, and its predecessor company was incorporated under the laws of Delaware in 1987. ATMI’s headquarters is located at 7 Commerce Drive, Danbury, Connecticut 06810, and the telephone number is (203) 794-1100.

     ATMI’s website can be found on the Internet at www.atmi.com. The website contains information about the Company and its operations. Copies of each of the Company’s filings with the SEC, including filings on Form 10-K, Form 10-Q, Form 8-K and Form S-8, and all amendments to those reports can be viewed and downloaded free of charge as soon as reasonably practicable after the reports and amendments are electronically filed with or furnished to the SEC by accessing www.atmi.com and clicking on Investor and then clicking on SEC Filing.

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     Any of our reports filed or furnished with the SEC can also be obtained in print by any stockholder who requests them from our Investor Relations Department:

Item 2. Properties

     The following table summarizes the location and size of ATMI’s various properties as of December 31, 2004:

(1)     Includes a new 68,000 square foot facility, which ATMI leased in the fourth quarter of 2004. During 2005, the Company will outfit this new facility and will move the operations of the high-purity packaging and delivery systems business from the old facility, also located in Bloomington, MN, to the new facility. The lease on the old facility will expire in August 2005 and is not expected to be renewed.

(2)     The operations of this facility have been moved to the Company’s new state-of-the-art materials manufacturing facility also in Burnet, Texas. Management expects to dispose of this site during 2005.

(3)     ATMI’s corporate headquarters. The lease expires in 2008.

(4)     This facility is primarily used by the buyer of the Company’s former outsourced parts cleaning and tool maintenance services business and the buyer of that business is paying a monthly occupancy fee to the Company for its continued use.

(5)     This facility is primarily used by the Company’s former environmental abatement equipment business and the buyer of that business is paying a monthly occupancy fee to the Company for its continued use.

ATMI also leases various sales offices throughout the world, each one of which occupies less than 5,000 square feet.

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Item 3. Legal Proceedings

     On July 11, 2003, ATMI’s subsidiary, Advanced Technology Materials, Inc., filed suit against Praxair, Inc., the parent company of Praxair Electronics, in the United States District Court for the Southern District of New York, charging it with infringing two patents ATMI holds for certain gas storage and delivery systems. ATMI is seeking damages and an injunction against Praxair marketing its UpTime system. On December 22, 2003, Praxair, Inc. and Praxair Technology, Inc. filed suit against ATMI, Inc. and Advanced Technology Materials, Inc. in the United States District Court for the District of Delaware alleging infringement of three patents owned by Praxair Technology, Inc. related to certain gas storage and delivery systems. Praxair is seeking damages and an injunction against ATMI marketing its VAC™ system.

     In addition, in the normal course of business, ATMI is involved in various proceedings and claims. Although the Company cannot determine the ultimate outcome of any of these legal proceedings at this time, management, including internal counsel, does not believe that the outcome of these proceedings, individually or in the aggregate, will have a material adverse effect on ATMI’s financial position or results of operations.

Item 4. Submission of Matters to a Vote of Security Holders

     No matter was submitted to a vote of security holders, through the solicitation of proxies or otherwise, during the fourth quarter of the fiscal year ended December 31, 2004.

PART II.

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

     The common stock of ATMI has traded on the Nasdaq National Market under the symbol ATMI since October 13, 1997, and the common stock of our predecessor company traded under that symbol from 1993 until October 12, 1997. The following table sets forth for the periods indicated the high and low sales price for the common stock as reported on the Nasdaq National Market:

     As of March 9, 2005, there were approximately 221 holders of record of the common stock.

     The Company has never declared or paid any cash dividends on its capital stock. The Company currently intends to retain all available earnings for use in its business and does not anticipate paying any cash dividends in the foreseeable future.

     The Transfer Agent and Registrar for ATMI is Equiserve Trust Company, N.A.

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Item 6. Selected Financial Data

     The following selected consolidated statements of operations for the years ended December 31, 2004, 2003, 2002, 2001 and 2000 and the consolidated balance sheet data as of December 31, 2004, 2003, 2002, 2001 and 2000 are derived from ATMI’s audited consolidated financial statements. The data set forth below should be read in conjunction with the consolidated financial statements and notes thereto and other financial information included elsewhere in this Form 10-K.