Electromagnetic wave detector, electromagnetic wave detector array, and manufacturing method of electromagnetic wave detector

An electromagnetic wave detector comprising:

• a semiconductor substrate;
• a first insulating film disposed on the semiconductor substrate and formed so as to expose a part of the semiconductor substrate;
• a first electrode disposed on the first insulating film;
• a two-dimensional material layer having a joint part forming a first Schottky junction with the semiconductor substrate in a part of the semiconductor substrate, the two-dimensional material layer extending from the joint part to the first electrode over the first insulating film;
• a second electrode in contact with the semiconductor substrate;
• and
• a control electrode disposed at least partly around the joint part in plan view to form a second Schottky junction with the semiconductor substrate,
• wherein the two-dimensional material layer has a portion that extends over an upper surface of the first insulating film to the first electrode and is in contact with the first insulating film,
• the two-dimensional material layer and the control electrode are disposed such that a depletion layer formed as a result of the connection of a depletion layer of the second Schottky junction to a depletion layer formed in the first Schottky junction when the first Schottky junction is reverse-biased covers an entire interface of the first Schottky junction, and
• the two-dimensional material layer is disposed so as to cover the control electrode with the first insulating film interposed between the two-dimensional material layer and the control electrode.

A manufacturing method of an electromagnetic wave detector, comprising:

• preparing a semiconductor substrate;
• forming a control electrode to form a first Schottky junction with the semiconductor substrate;
• forming an insulating film on the semiconductor substrate, the insulating film exposing a part of the semiconductor substrate;
• forming a first electrode on the insulating film;
• forming a second electrode in contact with the semiconductor substrate;
• and
• forming a two-dimensional material layer having a joint part forming a second Schottky junction with the semiconductor substrate in a part of the semiconductor substrate, the two-dimensional material layer extending from the joint part to the first electrode over the insulating film, wherein
• the forming a two-dimensional material layer causes the control electrode to be disposed at least partly around the joint part in plan view,
• the two-dimensional material layer has a portion that extends over an upper surface of the first insulating film to the first electrode and is in contact with the first insulating film,
• the two-dimensional material layer and the control electrode are disposed such that a depletion layer formed as a result of the connection of a depletion layer of the second Schottky junction to a depletion layer formed in the first Schottky junction when the first Schottky junction is reverse-biased covers an entire interface of the first Schottky junction, and
• the control electrode is disposed all around the joint part in plan view.