Sumitomo Chemical Company, Limited

Sciocs Company Limited

Hosei University

Yasuhiro Yamamoto

Hiroshi Ohta

Fumimasa Horikiri

Tohru Nakamura

Tomoyoshi Mishima

A semiconductor device includes a semiconductor member having a mesa structure in which a first semiconductor layer and a second semiconductor layer are laminated on each other and having a pn junction; an insulating film disposed on a side surface of the mesa structure and on an outside upper surface of the mesa structure; a first electrode connected to the second semiconductor layer on the upper surface of the mesa structure, and extends on the side surface of the mesa structure and on the outside upper surface of the mesa structure on the insulating film; and a second electrode connected to the first semiconductor layer on a lower surface of the first semiconductor layer, and having a capacitance of the insulating film when a reverse bias voltage is applied between the first electrode and the second electrode, so that a first voltage applied to the insulating film between a corner position (a first position) where the side surface of the insulating film disposed on the side surface of the mesa structure and the upper surface of the insulating film disposed on the outside upper surface of the mesa structure are connected to each other, and a corner position (a second position) where the side surface of the mesa structure and the outside upper surface of the mesa structure are connected to each other, is equal to or smaller than a second voltage applied to the first semiconductor layer between a pn junction interface (a third position) in a lower part of a region where the first electrode is in contact with the second semiconductor layer, and a position directly under the third position (a fourth position) at a height of the second position.

Semiconductor device

There is provided a semiconductor device, including: a semiconductor member having a mesa structure in which a second semiconductor layer having one of a p-type conductivity type and an n-type conductivity type is laminated on a first semiconductor layer having the other one of the p-type conductivity type and the n-type conductivity type, so that the second semiconductor layer is exposed on an upper surface of the mesa structure, a pn junction interface is exposed on a side surface of the mesa structure, and the first semiconductor layer is exposed on an outside upper surface of the mesa structure; an insulating film disposed on a side surface of the mesa structure and on an outside upper surface of the mesa structure; a first electrode electrically connected to the second semiconductor layer on the upper surface of the mesa structure, and extends on the side surface of the mesa structure and on the outside upper surface of the mesa structure on the insulating film; and a second electrode electrically connected to the first semiconductor layer on a lower surface of the first semiconductor layer, wherein the insulating film is constituted including a first insulating layer and a second insulating layer, the first insulating layer is disposed so as to cover a corner portion where the side surface of the mesa structure and the outside upper surface of the mesa structure are connected to each other, the second insulating layer is disposed so as to cover the pn junction interface exposed on the side surface of the mesa structure, or is disposed to constitute an entire thickness of the insulating film directly under the electrode end of the first electrode so as to cover the area directly under the electrode end, the relative dielectric constant of the second insulating layer is equal to or larger than the relative dielectric constant of the semiconductor member, and the relative dielectric constant of the first insulating layer is smaller than the relative dielectric constant of the second insulating layer.

Growing community of inventors

Koganei, Japan

Yasuhiro Yamamoto