| 摘要 |
PURPOSE:To form an insulated gate field effect transistor of ultrafine size without punch-through by using 2-valency ions in case of implanting ions on the channel region of the treansistor. CONSTITUTION:A field oxide film 2 is formed on an N type Si substrate 1, then photoetched, P type impurity is diffused, and source 3 and drain 4 of a P-channel MOS transistor are formed. Then, before forming a gate oxide film, 2-valency ions 8 are implanted. When using a crystalline surface 100 N type Si substrate, ion channeling effect is directed in the direction of ion implanting in the crystalline surface direction (100) at the maximum. To prevent a punch-through, the dosage is necessarily set at approx. 10<11>/cm<3>, and 2-valence impurity region 9 is formed in depth of approx. 0.5micron from the surface of the Si substrate. Then, a gate oxide film 5 is formed, a contacting region 10 is formed on the source 3 and the drain 4, and wirings 11 are formed, thereby forming a P-channel MOS transistor. |
