| 摘要 |
988,341. Semi-conductor devices. SIEMENS-SCHUCKERTWERKE A.G. Oct. 25, 1963 [Dec. 7, 1962], No. 42290/63. Heading H1K. A P-type zone in a body of Group IV semi - conductor material is produced by heating the body and a source of impurity having precipitated thereon a monoxide of the semi-conductor material, in a treatment vessel. Fig. 2 shows a scaled quartz vessel 4 containing discs 6 of silicon and an impurity source 5 consisting of a drop of gallium in a piece of silicon; the vessel 4 is shown in two positions in a furnace the temperature along the furnace being indicated by the temperature curve. As shown in position I, the silicon discs are at 1230‹ C. and the gallium source at 1050‹ C. while in position II the discs are still at 1230‹C., but the gallium is at 950‹ C. In the process, the vessel 4 is inserted into the furnace in position 1 and silicon monoxide forms at the quartz/silicon interface and precipitates in the region which is at 1050‹ C., i.e. on the gallium. After a period of 10 minutes to 1 hour the vessel is moved to position II for 30 to 48 hours when gallium diffuses into the silicon. The process may be carried out in vacuo or under a protective gas. The Specification also refers to aluminium and boron as impurities and germanium as semiconductor. The monoxide acts as a transport medium and facilitates accurate control of the diffusion process. |
