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Effect of Oxidizer on the Polishing in Cadmium Telluride CMP

카드뮴 텔룰라이드 CMP 공정에서 산화제가 연마에 미치는 영향

  • Shin, Byeong Cheol (School of Mechanical Engineering, Pusan National University) ;
  • Lee, Chang Suk (School of Mechanical Engineering, Pusan National University) ;
  • Jeong, Hae Do (School of Mechanical Engineering, Pusan National University)
  • Received : 2014.09.19
  • Accepted : 2014.12.29
  • Published : 2015.01.01

Abstract

Cadmium telluride (CdTe) is being developed for thin film of the X-Ray detector recently. But a rough surface of the CdTe should be improved for resolution and signal speed. This paper shows the study on the improvement of surface roughness and removal rate by applying Chemical Mechanical Polishing. The conventional potassium hydroxide (KOH) based colloidal silica slurry could not realize a mirror surface without physical defects, resulting in low material removal rate and many scratches on surface. In order to enhance chemical reaction such as form oxidized layer on the surface of cadmium telluride, we used hydrogen peroxide ($H_2O_2$) as an oxidizer. Consequently, in case of 3 wt% concentration of hydrogen peroxide, the highest MRR (938 nm/min) and the lowest surface roughness ($R_{p-v}=10.69nm$, $R_a=0.8nm$) could be obtained. EDS was also used to confirm the generated oxide of cadmium telluride surface.

Keywords

References

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