摘要 |
A semiconductor device, for example a CMOS, includes a semiconductor substrate 1 having a denuded region 2 and a bulk-defect region 3 and semiconductor elements 4 and 5. Element 4 may include a P well 15 while element 5 may include P<+> - type source or drain region (9, 10). To minimise or eliminate leak current at the PN junction 12 the distance from the surface of the substrate 1 to the surface of the bulk-defect region 3 varies in response to the nonuniform depth of the semiconductor elements 4 and 5. The device may be made by selectivly forming forming the bulk-defect region 3 with a high oxygen concentration and a nonuniform depth that varies in response to the nonuniform depth of the elements and forming the elements above the bulk-defect region. |