Targets For Applied Material Endura™ and Centura™ Sputtering Systems
Applied Materials’ Endura targets have been the focus of continuing refinement and enhancement within Praxair MRC for a number of years. Over the range of cathodes and configurations for the Endura family of PVD tools, Praxair MRC has concentrated on designing and optimizing its metals and alloys for optimal performance and consistent thin film characteristics.
Metals and alloy targets for IC production
Foremost, Praxair MRC’s CCH Do technology has been applied to aluminum alloys to achieve the Applied Materials Level III certification. In meeting this level of performance, Clean Metal Processing is employed to provide an inclusion-free starting billet material. Grain structure and crystallographic texture has been optimized through controlled experiments and testing has been completed on its 8" capable Endura sputtering tool. Testing was conducted to identify the impact of target metallurgical processing on sputtering performance and thin film quality. High purity, 99.9995% pure, aluminum alloys such as the industry standard Al 0.5% Cu has an optimized grain size of less than 50 m m and a weakly textured cubic structure. With the ideal structure identified, homogeneity and consistency is assured through extensive evaluation and the use of SPC in the manufacturing process.
These processes are applied to the Durasource and ALPS cathode target configuration. Praxair MRC developed the single piece MonoBlocTM design avoiding the use of e-beam welding and the associated risks of virtual leaks due to inconsistent weld formation. For the ALPS design, MRC's finite element modeling has lead to a high strength assembly optimized for extended target life. Praxair MRC’s proprietary MightyBond process is used to produce a bond strength equivalent to a solid state metallurgical diffusion bond, while maintaining the grain structure developed by the CCH Do processing.
Contact and barrier materials, Ti and WTi, are similarly produced under CCH processing methodologies. Praxair MRC’s CCH Do and Do* titanium, whether used in a Durasource configuration. TTN, Co-Ti or Vectra has structures optimized for highest performance and minimum particle generation. For high power deposition, Praxair MRC’s high strength diffusion like IntegraBond provide the industry’s highest bond strengths thus eliminating risk associated with target de-bonding. Praxair MRC’s proprietary Embedded Ti designs for G-series cathodes significantly increase target life by as much as 25% as compared to standard designs.
From Praxair MRC’s metallurgical processing experience with magnetic alloys used in data storage industry, cobalt and nickel Endura targets can be manufactured with low permeability and increased magnetic leakage flux. This enables Praxair MRC to offer up to 3 mm thick targets for extended life.
For copper based IC production, Praxair MRC has applied CCH processing techniques to produce fine grained, texture controlled structures for both tantalum and copper sputtering targets. Using the proprietary MightyBond™process, Praxair MRC is able to bond copper targets with very high strength while maintaining the fine microstructure.
By extensive use of DOE (Design of Experiments) techniques for product design and SPC (Statistical Process Control) in manufacturing, Praxair MRC's products are consistent target-to-target, lot-to-lot. Analytical capability is a strong feature of the support MRC can provide. A variety of techniques including GDMS (Glow Discharge Mass Spectrometry) are utilized in the Praxair MRC laboratory. A Certificates of Analysis (COA) is issued for each target and these detail the ACTUAL impurity level detected. Comparison of the results with the customer specification is completed by the Laboratory Information Management System (LIMS) developed by MRC. The LIMS is also used to generate SPC data.
Praxair MRC has offices and agents in all of the key semiconductor fabrication areas of the world. In addition Praxair MRC has established manufacturing facilities on three continents to supply high purity sputtering targets to serve the "local" market. Customers' needs are fully understood and timely service is provided. With strong technological expertise in the art of sputtering and metallurgical knowledge stretching back years, Praxair MRC is ideally suited to provide and support the targets for the Applied Materials Endura 5500 PVD system.