半导体基板及半导体基板之制造方法;SEMICONDUCTOR SUBSTRATE AND METHOD FOR MAKING A SEMICONDUCTOR SUBSTRATE

摘要

本发明提供一种下述半导体基板：第1超晶格层具有复数之由第1层及第2层而成的第1单元层，第2超晶格层具有复数之由第3层及第4层而成的第2单元层，第1层系由Alx1Ga1-x1N(0<x1≦1)而成，第2层系由Aly1Ga1-y1N(0≦y1<1，x1>y1)而成，第3层系由Alx2Ga1-x2N(0<x2≦1)而成，第4层系由Aly2Ga1-y2N(0≦y2<1，x2>y2)而成，第1超晶格层之平均晶格常数与第2超晶格层之平均晶格常数相异，于选自第1超晶格层及第2超晶格层之1层以上之层中，以超过7×10 18 〔atoms/cm 3 〕之密度含有提升耐电压性之杂质原子。;x1≦1), the second layer includes Aly1Ga1-y1N (0≦y1<1、x1>y1), the third layer includes Alx2Ga1-x2N (0<x2≦1), and the fourth layer includes Aly2Ga1-y2N (0≦y2<1、x2>y2). The first superlattice layer has an average lattice constant different from the average lattice constant of the second superlattice layer. One or more than one layer selected from the first superlattice layer and the second superlattice layer contains dopant (impurity) atoms having a density of over 7×10 18 [atoms/cm 3 ] for enhancing a strength against voltage.