MANUFACTURE OF SEMICONDUCTOR MECHANICAL QUANTITY SENSOR

摘要

PURPOSE: To make it possible to prevent the warp of a movable section of a beam structure. CONSTITUTION: A silicon oxide film 22 is formed as a sacrifice layer on a silicon substrate 17. On the silicon oxide film 22, a polysilicon thin film 24 is prepared as the one for forming a movable section. Then, phosphorus ions are implanted into the polysilicon thin film 24. At that time, the doping is so done that the profile of the phosphorus ion distribution may be a specified one in the film thickness direction by changing the accelerating voltage. After that, the silicon oxide film 22 is removed and then a movable section (movable gate electrode) of a beam structure is located above the silicon substrate 17, a specified distance removed from the silicon substrate 17. In the silicon substrate 17, fixed electrodes (a source and a drain electrode) are formed.