Silicon carbide semiconductor device and a method of manufacturing the silicon carbide semiconductor device
摘要
說(shuō)明書
The n?-type drift layer 3 may have a nitrogen concentration of, for example, about 3×1014/cm3. The nitrogen concentration of the n?-type drift layer 3 is lower than the nitrogen concentration of the n-type starting substrate 1, the nitrogen concentration of the n-type buffer layer 2, and an aluminum concentration of the p-type anode layer 4. The nitrogen concentration of the n?-type drift layer 3 is uniform from an interface 11 between the n-type buffer layer 2 and the n?-type drift layer 3 to a pn junction surface (interface) 12 between the p-type anode layer 4 and the n?-type drift layer 3. In other words, nitrogen concentrations of the first to the third n?-type layers 21 to 23 are equal. The p-type anode layer 4 may have a thickness t4 of, for example, about 2 μm. The aluminum concentration (aluminum density) of the p-type anode layer 4 may be, for example, in a range from about 1×1018/cm3 to 1×1020/cm3.
