[18p-B301-1~10] 13.1 Fundamental properties, surface and interface, and simulations of Si related materials

[18p-B301-5] Evaluation of trace metal contamination in SiO₂ by Pulse Photoconductivity Method

〇(M1)Shotaro Kuzukawa¹, Takahiro Ono¹, Tatsuro Kawano¹, Hiroki Matsuyama¹, Kazuhiro Kobayashi¹, Hiroshi Kubota¹, Takeshi Hashishin¹, Masao Yoshioka², Moriya Miyashita³, Takahiro Maeta³ (1.GSST Kumamoto Univ., 2.Faculty of Technology Kumamoto Univ., 3.GlobalWafers Japan)

Keywords:evaluation, contamination, silicon

At advanced semiconductor devices, trace metal contamination in wafers is known to adversely affect electrical characteristics. For example at image sensors, due to the influence of ultra-trace metal contamination, electrical signals are output in spite of non-light-receiving, which is recognized as white flaws. As a method of reducing the contamination in the device formed region, gettering by BMD(Bulk Micro Defect) in wafers is known. However, it is an issue that there is no method for high-sensitive analyzing of contamination in the wafer surface layer which is the device active region by non-destructive. Pulse Photoconductivity Method (PPCM) is effective on measuring the electrical conductivity of silicon dioxide film in the wafer surface layer, and we report the result of attempting evaluation of gettering ability by BMD in the wafer applying this method. We also propose the evaluation of ultra-trace contamination.