Semiconductor device having trenches and process for same
First Claim
1. A process for a semiconductor device having a trench including:
- the step of forming a trench in a main surface of a semiconductor substrate;
the step of forming a first insulating film on the main surface of said semiconductor substrate in one step, or in a plurality of divided steps, so as to fill in said trench and to have a void in said trench;
the step of forming an aperture which reaches to the inside of said trench in said first insulating film by connecting said void with the outside of said trench through an anisotropic etching in said first insulating film so that the upper edge corner parts of said aperture in said first insulating film have a more round edge than the upper edge corner parts of said trench and of reducing the film thickness of said first insulating film on the main surface of said semiconductor substrate; and
the step of forming a second insulating film on the main surface of said semiconductor substrate in one step, or in a plurality of divided steps, so as to fill in said aperture.
1 Assignment
0 Petitions
Accused Products
Abstract
The elements and the trenches are arranged alternately, in repetition, on the main surface of a semiconductor substrate, each of the plurality of elements arranged alternately, in repetition, with the trenches has a configuration (for example, STM) which operates in the same operational mode, and an insulating layer, which is filled into the trenches, and doesn'"'"'t have a void at a position (the position shallower than the broken line L) shallower than the pn junction to which the largest electric field in the element is applied. Thereby, a semiconductor device and a process for the same, where voids inside of the trenches can be reduced and the film thickness of the insulating film, for filling in the trenches which remain on the surface of the semiconductor substrate, can be made thinner, can be gained through a simple method.
52 Citations
8 Claims
-
1. A process for a semiconductor device having a trench including:
-
the step of forming a trench in a main surface of a semiconductor substrate;
the step of forming a first insulating film on the main surface of said semiconductor substrate in one step, or in a plurality of divided steps, so as to fill in said trench and to have a void in said trench;
the step of forming an aperture which reaches to the inside of said trench in said first insulating film by connecting said void with the outside of said trench through an anisotropic etching in said first insulating film so that the upper edge corner parts of said aperture in said first insulating film have a more round edge than the upper edge corner parts of said trench and of reducing the film thickness of said first insulating film on the main surface of said semiconductor substrate; and
the step of forming a second insulating film on the main surface of said semiconductor substrate in one step, or in a plurality of divided steps, so as to fill in said aperture. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
Specification