Production of Reduced Defect Density (112) Silicon Wafers Utilizing Ultra- Gentle, Chemical Mechanical Smoothening (CMS) Process

As the epi quality of HgCdTe layers is dependent on the quality of silicon surfaces, it is imperative that the (112) Si surfaces be pristine and devoid of defects. Unfortunately, the commercial available (112) Si surfaces are typically poor quality due to the presence of large number of COP (crystal originated particle) defects. Such defects arise during crystal growth and are further delineated by the standard CMP (chemical mechanical polishing) process used in the industry. Thus, to enhance the crystalline quality of (112) wafers, new methods to eliminate COP defects, and the development of ultra-smooth and ultra-gentle CMP polishing techniques that are optimized for (112) wafers will be explored as part of this project. Sinmat's technology is based on combination of unique thermal annealing and polishing process. Using unique particles and chemical additives, ultra-gentle and ultra-smooth polishing process for (112) substrates will be developed.