| 摘要 |
PURPOSE:To form a capacitance insulating film in excellent breakdown strength, leakage characteristics and insulation breakdown characteristics with time while enhancing the reliability of the title semiconductor integrated circuit device by a method wherein a silicon oxide film is formed in a groove part of a semiconductor substrate to be steam-processed later. CONSTITUTION:A groove 102 is formed in a semiconductor substrate 101 comprising silicon and after finishing a process such as ion implantation, a silicon oxide film 103 is formed by pressure-reduced CVD process using a mixed gas containing SiH4 and N2O as reactive gas at the temperature of 800-850 deg.C and the pressure of 0-100 Pa. At this time, the silicon oxide film 103 is not made thinner at the groove corner parts thereby enabling the silicon oxide film in even film thickness in the groove to be formed due to the pressure reduced CVD process. Next, the heat treatment process is performed at 750 deg.C for around 5 minutes in steam atmosphere. Through these procedures, the deterioration in the breakdown strength, leakage characteristics and the insulation breakdown characteristics with time as the capacitance insulating film can be avoided while enhancing the reliability of the title device. |
