| 摘要 |
PURPOSE:To eliminate a detection error caused by the difference of the thermal expansion coefficient from that of a case and the like and improve pressure detecting accuracy and sensitivity by a method wherein a conductive layer which constitutes a pressure detector is used as 1st electrode and a variable capacitance structure is composed of the 1st electrode and a metal thin film which is provided facing the 1st electrode with a space between as the 2nd electrode. CONSTITUTION:An N-type well 3 is formed on a semiconductor substrate 1 and a P<+> type conductive layer 15 is formed as 1st electrode in a region defined by a silicon oxide film 5 as a field insulating film. Moreover, a platinum thin film 9, which is 2nd electrode and insulated by an acid resistant silicon nitride film 6, is formed so as to hold a space 21 between the P<+> type conductive layer 15 and itself and a capacitance is composed of the 1st electrode 15 and the 2nd electrode 9. Then a CVD silicon oxide film 11, a low concentration PSG film 13 and a CVD silicon nitride film 14 are deposited and an aperture 20 formed in the platinum thin film 9 is sealed and the space 21 mentioned above is enclosed.
|
