| 摘要 |
<p>After selectively forming a P+-type gate regions (14) in the upper surface of a first N--type semiconductor substrate (10), gate electrodes are selectively formed on the gate regions (14). A P+-type layer (12) is formed in the lower surface of the substrate (10). Recesses (26) which can house the gate electrodes (30) are formed in the lower surfaces of the semiconductor substrate (20) and an N+-type layer (22) is formed in the upper surface thereof. After removing impurities from the surfaces of the first and second semiconductor substrates (10 and 20) by RCA cleaning, the surfaces are cleaned with pure water and dried by a centrifugal dryer. Then the substrates (10 and 20) are joined to each other by heating the substrates (10 and 20) at 700-1.100 °C in an H¿2? atmosphere while the upper surface of the substrate (10) is in contact with projections (29) on the lower surface of the substrate (20). Thus a static induction thyrister, static induction transistor, or gate turn-off thyristor in which gate regions and gate electrodes are buried in a semiconductor substrate can be obtained.</p> |
