| 摘要 |
A monocrystalline Si chip (25) of N type is provided with a SiO2 mask (26), pierced by a window (27), then is placed in a closed diffusion furnace containing pure gallium and gallium arsenide. After the diffusion processing, the chip contains an N-type core (31), a P- type envelope (30) formed by diffusion of the gallium through the mask and an N-type region (32) formed by diffusion of the arsenic through the window (27). Next, the mask (26) is dissolved and the chip is placed in an open diffusion furnace and is exposed to water vapour, which forms a new SiO2 coating over the whole surface and accentuates the differentiation of the P and N regions. Next, the window (27) is reformed and successive layers of Ni and Au are deposited thereon. Finally, the chip is abraded to expose the P and N regions. The device thus obtained is used as a thyristor. <IMAGE>
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