Semiconductors chemical manufacturing processes

Oxygen. High purity oxygen for use in semiconductor device manufacture is produced in relatively small quantities compared to nitrogen. There are two different purification processes in general use for manufacturing the gas distillation and chemical conversion plus adsorption. 

Process safety management has been applied primarily in the chemical process industries. However, the concepts of PSM, and the approaches used for implementing PSM, can be applied equally well to any manufacturing process that uses chemical products. Manufacturing industries as diverse as semiconductor manufacturing 2md food processing can, and do, apply PSM to improve safety and operations. 

In a modern industrialised society the analytical chemist has a very important role to play. Thus most manufacturing industries rely upon both qualitative and quantitative chemical analysis to ensure that the raw materials used meet certain specifications, and also to check the quality of the final product. The examination of raw materials is carried out to ensure that there are no unusual substances present which might be deleterious to the manufacturing process or appear as a harmful impurity in the final product. Further, since the value of the raw material may be governed by the amount of the required ingredient which it contains, a quantitative analysis is performed to establish the proportion of the essential component this procedure is often referred to as assaying. The final manufactured product is subject to quality control to ensure that its essential components are present within a pre-determined range of composition, whilst impurities do not exceed certain specified limits. The semiconductor industry is an example of an industry whose very existence is dependent upon very accurate determination of substances present in extremely minute quantities. 

Arsine is an extremely toxic, colorless gas used extensively in the semiconductor industry. Arsine also is used in mining and manufacturing processes involving arsenicals and in paints and herbicides containing arsenicals (Risk and Fuortes 1991). Annual production has been estimated at over 10,000 pounds and is likely increasing with greater use in the semiconductor industry (U.S. EPA 1980). The physical and chemical data for arsine are shown in Table 2-2. 

Details of the chemical oxidation process are discussed in Section 5.2. The stringent requirements concerning metal contamination and the trend to more environmentally friendly processing are a constant force to improve cleaning procedures in today s semiconductor manufacturing [Me4, Sal, Ohl]. 

The acceptance of chemical mechanical planarization (CMP) as a manufacturable process for state-of-the-art interconnect technology has made it possible to rely on CMP technology for numerous semiconductor manufacturing process applications. These applications include shallow trench isolation (STI), deep trench capacitors, local tungsten interconnects, inter-level-dielectric (ILD) planarization, and copper damascene. In this chapter. 

Currently, American semiconductor manufacturers are losing the battle with Japan and Korea in the production and sales of reliable, low-priced IC devices or chips. The failures and low yields that have hindered U.S. efforts are partially caused by the inadequate understanding of the chemical processes in semiconductor production and the lack of good quality controls for chemicals and processes. 

Most companies producing ICs today have been quite lax in the quality control of the liquid chemicals used in their processes. These chemicals include acids, bases, buffered etches, photoresists, and organic solvents. Essentially, the producers of ICs have left the quality control of these materials to the chemical manufacturers. Specifications for chemicals are set by SEMI (Semiconductor Equipment Manufacturers International) and are generally met by all chemical manufacturers. The level of metallic contaminations that can exist in U.S. chemicals ranges from 0.1 to 1 ppm. If the levels of metallic impurities were actually this high, U.S. manufacturers would not be able to produce integrated circuits. 

NQC A chemical used as the raw material of a photosensitive substance, which is one of several components of a photoresist used in the manufacturing process of semiconductors or liquid crystal displays. 

Surfaces and interfaces chemistry is the study of the structure and reactivity of liquid and solid surfaces. The surfaces may be extended or may be limited to the nanometer scale. The surface, often a transition metal, may be a catalyst for a chemical reaction. Such studies provide the fundamental principles of the commercially important area of heterogeneous catalysis, which is essential to fuel and metal production, food processing, and commodity chemical manufacturing. The surface may also be consumed as a reactant, such as in semiconductor etching. These studies provide the basic chemistry of the manufacturing of electronic components and devices. 

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