US 2003/0148559 A1 · Semiconductor device and the method of manufacturing the same

Abstract

A semiconductor device includes an improved drain drift layer structure of alternating conductivity types, that is easy to manufacture, and that facilitates realizing a high current capacity and a high breakdown voltage and to provide a method of manufacturing the semiconductor device. The vertical MOSFET according to the invention includes an alternating-conductivity-type drain drift layer on an n+-type drain layer as a substrate. The alternating-conductivity-type drain drift layer is formed of n-type drift current path regions and p-type partition regions alternately arranged laterally with each other. The n-type drift current path regions and p-type partition regions extend in perpendicular to n+-type drain layer. Each p-type partition region is formed by vertically connecting p-type buried diffusion unit regions Up. The n-type drift current path regions are residual regions, left after connecting p-type buried diffusion unit regions Up, with the conductivity type thereof unchanged. The alternating-conductivity-type drain drift layer is formed by repeating the step of epitaxial layer growth and the step of implanting p-type impurity ions and by diffusing the impurity ions at once from the impurity sources located on multiple levels.

Claims19

Dependent claims

A semiconductor device comprising:

an alternating conductivity type layer comprising vertical first regions of a first conductivity type and vertical second regions of a second conductivity type;
the vertical first regions and the vertical second regions being alternately arranged with each other;
each of the vertical first regions or each of the vertical second regions comprising epitaxially grown layers laminated with each other;
and
each of the vertical second or each of the vertical first comprising buried diffusion unit regions connected vertically with each other.

2 more elements

A method of manufacturing a semiconductor device including an alternating conductivity type layer formed of vertical first regions of a first conductivity type and vertical second regions of a second conductivity type, the vertical first regions and the vertical second regions being alternately arranged with each other, each of the vertical first regions or each of the vertical second regions being formed of epitaxially grown layers laminated with each other, and each of the vertical second regions or each of the vertical first regions being formed of buried diffusion unit regions connected vertically with each other, the method comprising the steps of:

(a) selectively implanting impurity ions of the second conductivity type or the first conductivity type into diffusion centers in the surface portion of a substrate;
(b) forming an epitaxially grown layer doped relatively lightly on the substrate;
(c) selectively implanting impurity ions of the second conductivity type or the first conductivity type into diffusion centers in the surface portion of the epitaxially grown layer;
(d) repeating the steps (b) and (c), whereby to form a laminate including a desired number of the diffusion centers aligned vertically;
and
(e) thermally diffusing the implanted impurity ions from the diffusion centers, whereby to connect the buried diffusion unit regions vertically with each other.

3 more elements

Dependencies are inferred from the claim text.

Semiconductor device and the method of manufacturing the same

Life of this patent

Semiconductor device and the method of manufacturing the same

Life of this patent

Abstract

Claims19