MANUFACTURE OF SEMICONDUCTOR DEVICE

• Main Author: KATSUBE MASAKI
• Format: Patent
• Language: English
• Published: 13.05.1994
• Edition: 5
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PURPOSE:To further improve insulation-breakdown-strength of a MISFET by farming a MISFET gate oxide film in the atmosphere containing no such halogen as chlorine while forming at least a part of other MISFETs in oxygen atmosphere containing halogen. CONSTITUTION:The surface of a semiconductor substrate 11 in the first and second element formation areas A and B surrounded by a selective oxide film 12 is exposed. Then, the surface of semiconductor substrate 11 is thermal- oxidized in the atmosphere containing chlorine and oxygen, so that the first SiO2 film 13 is formed, and after that a polycrystalline silicon film 14 is grown over the entire surface. Then, a photoresist 15 is applied, exposed, and developed, so that a pattern for exposing the polycrystalline silicon film 14 in the first element area A is formed, after that, the polycrystalline silicon film 14 and the SiO2 film 13 are removed. After the photoresist 15 is peeled off, the surface of the semiconductor substrate 11 and polycrystalline silicon film are thermally-oxidized in the dry oxygen atmosphere containing no halogen, so the second SiO2 film 17 and the third SiO2 film 16 are formed an the surface of substrate 11 and polycrystalline silicon film 14, respectively.