| 摘要 |
PURPOSE:To make it possible to manufacture a polycrystalline Si MOS type field-effect transistor characterized by a small OFF current, a small absolute value of threshold voltage and a large operating current, by using disilane or trisilane as a reacting gas, performing deposition in an amorphous state at a specified temperature, performing a heat treatment and polycrystallization. CONSTITUTION:Decomposition is performed at a temperature of 550 deg.C or less by using disilane or trisilane as a reacting gas, and deposition is performed under an amorphous state. Heat treatment is performed at a temperature higher than the deposition temperature, and a polycrystalline state is obtained. For example, an amorphous Si film 13 is deposited on an SiO2 film 12 on a P-type Si substrate 11 by an LPCVD method by using Si2H6 gas as a reacting gas at a temperature of 520 deg.C. The film is patterned in an island shape. Thereafter, an SiO2 film 14 is deposited. Heat treatment is performed at 900 deg.C, and a gate oxide film is obtained. Then, P ions are implanted in the polycrystalline Si 13. A polycrystalline Si film is deposited by using SiH4 as a reacting gas, and a gate electrode 15 is formed. Then, an SiO2 film is formed by heat treatment. BF2 ions are implanted, and P-type high concentration impurity regions for a source, a drain and a gate are formed. |
