TY - GEN
T1 - Development of lapping and polishing technologies of 4H-SiC wafers for power device applications
AU - Yashiro, Hirokatsu
AU - Fujimoto, Tatsuo
AU - Ohtani, Noboru
AU - Hoshino, Taizo
AU - Katsuno, Masakazu
AU - Aigo, Takashi
AU - Tsuge, Hiroshi
AU - Nakabayashi, Masashi
AU - Hirano, Hosei
AU - Tatsumi, Kohei
PY - 2009/1/1
Y1 - 2009/1/1
N2 - The development of lapping and polishing technologies for SiC single crystal wafers has realized the fabrication of an extremely flat SiC wafer with excellent surface quality. To improve the SiC wafer flatness, we developed a four-step lapping process consisting of four stages of both-side lapping with different grit-size abrasives. We have applied this process to lapping of 2-inch-diameter SiC wafers and obtained an excellent flatness with TTV (total thickness variation) of less than 3 μm, LTV (local thickness variation) of less than 1 μm, and SORI smaller than 10 μm. We also developed a novel MCP (mechano-chemical polishing) process for SiC wafers to obtain a damage-free smooth surface. During MCP, oxidizing agents added to colloidal silica slurry, such as NaOCl and H2O2, effectively oxidize the SiC wafer surface, and then the resulting oxides are removed by colloidal silica. AFM (atomic force microscope) observation of polished wafer surface revealed that this process allows us to have excellent surface smoothness as low as Ra=0.168 nm and RMS=0.2 nm.
AB - The development of lapping and polishing technologies for SiC single crystal wafers has realized the fabrication of an extremely flat SiC wafer with excellent surface quality. To improve the SiC wafer flatness, we developed a four-step lapping process consisting of four stages of both-side lapping with different grit-size abrasives. We have applied this process to lapping of 2-inch-diameter SiC wafers and obtained an excellent flatness with TTV (total thickness variation) of less than 3 μm, LTV (local thickness variation) of less than 1 μm, and SORI smaller than 10 μm. We also developed a novel MCP (mechano-chemical polishing) process for SiC wafers to obtain a damage-free smooth surface. During MCP, oxidizing agents added to colloidal silica slurry, such as NaOCl and H2O2, effectively oxidize the SiC wafer surface, and then the resulting oxides are removed by colloidal silica. AFM (atomic force microscope) observation of polished wafer surface revealed that this process allows us to have excellent surface smoothness as low as Ra=0.168 nm and RMS=0.2 nm.
KW - 4H-SiC
KW - Atomic force microscopy
KW - Auger electron spectroscopy
KW - Lapping
KW - LTV
KW - Mechano-chemical polishing
KW - SORI
KW - TTV
UR - http://www.scopus.com/inward/record.url?scp=63849243259&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=63849243259&partnerID=8YFLogxK
U2 - 10.4028/3-908453-11-9.819
DO - 10.4028/3-908453-11-9.819
M3 - Conference contribution
AN - SCOPUS:63849243259
SN - 9780878493579
T3 - Materials Science Forum
SP - 819
EP - 822
BT - Silicon Carbide and Related Materials 2007
A2 - Suzuki, Akira
A2 - Okumura, Hajime
A2 - Fukuda, Kenji
A2 - Nishizawa, Shin-ichi
A2 - Kimoto, Tsunenobu
A2 - Fuyuki, Takashi
PB - Trans Tech Publications Ltd
T2 - 12th International Conference on Silicon Carbide and Related Materials, ICSCRM 2007
Y2 - 14 October 2007 through 19 October 2007
ER -