| 摘要 |
PROBLEM TO BE SOLVED: To provide an SOI substrate which is provided with an SOI layer superior in uniformity of film thickness, crystallinity and electrical characteristics. SOLUTION: Hydrogen ions are implanted at a dose of 8×10<SP>16</SP>-4×10<SP>17</SP>atoms/cm<SP>2</SP>to form an ion implantation layer 11 in a single crystal silicon substrate 10. The silicon substrate 10 and a quartz substrate 20 are bonded and they are heated at comparatively low temperature of 150°C or more and 300°C or less. The heating treatment results in thermal stress due to a difference in thermal expansion coefficient between both substrates 10 and 20, and the chemical bond of silicon atoms in the ion implantation layer 11 is weakened. Thermal impact, vibration impact or mechanical impact is given to the ion implantation layer 11 weakened by the heat treatment from the outside, so as to peel off a silicon thin film and to obtain an SOI layer 12 on the quartz substrate 20. The heat treatment temperature is limited to 300°C or less, so that significant diffusion of hydrogen atoms in the silicon crystal is not generated, and no surface roughness of the SOI layer is also produced. COPYRIGHT: (C)2007,JPO&INPIT
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