Trench type pip capacitor, power integrated circuit device using the capacitor, and method of manufacturing the power integrated circuit device

A method of manufacturing a power integrated circuit device, comprising:

• forming a trench from a surface of a semiconductor layer toward an inner part of the semiconductor layer;
• forming an isolating insulation layer on an inner wall of the trench:
• forming a lower electrode comprising a first polysilicon filled in the trench, the isolating insulation layer electrically isolating the first polysilicon from the semiconductor layer;
• forming a capacitor comprising a capacitive insulation layer formed on the first polysilicon;
• forming an upper electrode comprising a second polysilicon that is formed on the capacitive insulation layer;
• and
• forming an output stage element which is a vertical power MOS semiconductor element with a trench gate structure,
• wherein the trench to be filled with the first polysilicon is formed simultaneously with a trench to deposit a gate of the vertical power MOS semiconductor element with the trench gate structure.

A method of manufacturing a power integrated circuit device comprising:

• (i) forming a trench-type PIP-type capacitor by:
• forming a trench from a surface of a semiconductor layer toward an inner part of the semiconductor layer;
• forming an isolating insulation layer on an inner wall of the trench:
• forming a lower electrode comprising a first polysilicon filled in the trench, the isolating insulation layer electrically isolating the first polysilicon from the semiconductor layer;
• forming a capacitor comprising a capacitive insulation layer formed on the first polysilicon;
• and
• forming an upper electrode comprising a second polysilicon that is formed on the capacitive insulation layer;
• and
• (ii) forming an output stage element that passes or interrupts main current and a control circuit for controlling the output stage element, the latter two components being formed on the same semiconductor layer on which the trench-type PIP capacitor is formed,
• wherein the capacitive insulation layer is a silicon oxide film formed by a chemical vapor deposition (CVD) method.