FIELD OF THE INVENTION

The present invention relates to a capacitor. The present invention particularly relates to a high withstand voltage Si capacitor.

BACKGROUND OF THE INVENTION

Japanese Patent Application Laid-Open No. 2014-241434 (Patent Document 1) describes an example of a capacitor. In the capacitor described in this document, a plurality of grooves are formed on the surface of a substrate region, and a dielectric film is formed so as to cover the uneven face generated by these grooves.

Patent Document 1: Japanese Patent Application Laid-Open No. 2014-241434

SUMMARY OF THE INVENTION

If the thickness of the dielectric layer is increased, the withstand voltage increases. However, when the thickness of the dielectric layer is excessively increased, the residual stress in the dielectric layer increases. When the residual stress is large, there is a possibility that the capacitor will crack or warp.

Therefore, an object of the present invention is to provide a capacitor that can withstand a high voltage and can be prevented from cracking or warping.

In order to achieve the object, the capacitor according to the present invention includes a substrate having a main surface with at least one of a recess or a projection, a dielectric film extending along the at least one of the recess or the projection and having an equivalent oxide thickness of 600 nm or more, and a conductor film covering at least part of the dielectric film.

According to the present invention, the capacitor can withstand a high voltage and can be prevented from cracking or warping.

