| 摘要 |
PURPOSE:To avoid generation of defective articles due to hot electron by applying an insulating film on an MOS IC forming a predetermined element region, diffusing P impurities on the film to perform gettering, and diffusing As impurities reducing the lifetime of the carrier on the back surface of the substrate. CONSTITUTION:Thick field SiO2 films 2 are formed on the peripheral edge parts of a P type Si substrate 1, and this gate SiO2 film 3 is applied on the surface of the substrate 1 encircled by the above film 2. A gate electrode 4 composed of polycrystal Si is formed at the central part of the SiO2 film 3. Then, by using the electrode 4 as a mask. As is diffused in the substrate 1 at both sides of the electrode 4 to form an N type source and drain regions 5 and 6. The full surfaces of these regions 5 and 6 are coated with an insulating film and P is diffused thereon to perform gettering. Then, a high impurities concentration layer on the surface layer is eliminated. Thereafter, on the back surface of the substrate 1, an As diffused layer 8 is formed to shorten the lifetime of the substrate 1, and a window is formed in the remaining film 7, while an Al internal wiring 9 being fitted to the electrode 4. |
