| 摘要 |
PURPOSE:To form a defectless layer on the surface of a substrate, and to enhance the characteristic and yield of the device by a method wherein after an well is formed, a heat treatment is performed at about 600-700 deg.C to provide a high density crystal defect layer in the Si substrate. CONSTITUTION:After the well 2 is formed in the Si substrate 1, when it is treated at 600-800 deg.C for 10-20hr, minute nuclei 11 are generated in the substrate according to deposition of O2. When the CMOSIC is formed according to the normal method, the deposited nuclei 11 grow into the crystal defect layer 12 by the treatment at about 1,000 deg.C to be performed when a field oxide film 3 is to be formed, and is formed in high density inside of the substrate. Because the layer 12 has the strong gettering effect to a minute defect and a heavy metal, contaminations thereof are removed to obtain the defectless layer on the surface of the substrate. Depth of the defectless layer is decided according to the temperature and the hours performed when the well is to be formed. According to this construction, reduction of a junction leakage current, increase of surface lifetime, and reduction of a consuming current of the MOS device can be obtained, and yield is also enhanced. |
