| 摘要 |
PURPOSE:To prevent a leakage current by forming an n-type impurity implanted layer for preventing the leakage current in the drain region of an n-channel transistor on the side surface of an element region before an element separation region is formed and performing a thermal process at 900 deg.C or below. CONSTITUTION:Oxide and nitride films 42 and 43, respectively, are formed in the element region of a semiconductor (silicon) substrate 41 provided on a sapphire substrate 21. Then, silicon 41 outside the element region is etched and an ion implantation for preventing a field inversion and the one for preventing a leakage current are conducted on the side surfaces of silicon 41 in the element region to form impurity layers 44. Thereafter, an element separation layer 28 is formed and a thermal process after the formation of a gate insulating film 29 is performed at 900 deg.C or below. |
