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硅是实用上十分重要的半导体材料。它的化合物遍布于自然界中,不象锗要考虑資源問題。硅之所以使人們感兴趣,主要还在于它有比較大的禁带寬度(硅的禁带寬度为1.21电子伏,锗为0.75电子伏),从而导致两个十分重要的結果。首先,由于硅有較大的禁带寬度,能在更高的溫度(>200℃)才变成本征性,因此硅半导体器件能在锗不能长期使用的溫度范围工作。其次,它的p-n結的反向电流比锗要低——低三个数量級,这一性貭在許多迴路应用中是很重要的。然而,提純硅却此提純锗困难得多。这是因为硅的熔点較高(锗的熔点是936℃,硅是1420℃),熔融时有高度的化学活泼性。硅中的某些杂貭有比較大的
Silicon is a very important practical semiconductor material. Its compounds are found in nature, unlike the germanium to consider the issue of resources. The reason why silicon is of interest to people is that it has a relatively large forbidden band width (the band gap of silicon is 1.21 electron volts and germanium is 0.75 electron volts), resulting in two very important results. First, because silicon has a larger bandgap and can become intrinsic at higher temperatures (> 200 ° C), silicon semiconductor devices can operate over the extended temperature range where germanium can not be used for a long time. Second, its p-n junction reverse current is lower than germanium - three orders of magnitude lower, this property 貭 in many loop applications is very important. However, the purification of silicon is much more difficult to purify with germanium. This is because silicon has a higher melting point (936 ° C for germanium and 1420 ° C for silicon) and is highly chemically reactive when melted. Some impurities in silicon are relatively large