| 摘要 |
PURPOSE:To facilitate the fine processing for a low voltage small current circuit and thereby to provide a composite integrated circuit device having the circuit in high integration density by configurating a low voltage, small current circuit comprising the field insulating film in such a thickness as is thinner than the thickness of field insulating film of a high voltage, large current circuit. CONSTITUTION:In a high voltage, large current circuit B, a thick oxide film 9 is remained, while in a low voltaga, small current circuit A, the oxide film 9 is cut thinner by the photo etching method etc. in accordance with a voltage value of such a low voltage power source or only the oxide film of a low voltage, small current circuit A is once removed and a thin oxide film 9 is newly grown again. Thereby, the very fine processing can be realized easily by the photo etching method etc. for the block having a thin oxide film and accordingly a composite integrated circuit comprising a low voltage, small current circuit with a high integration density can be manufactured easily. |
