Device configured to have a nanowire formed laterally between two electrodes and methods for forming the same

A method for forming a device having a nanowire formed laterally between two electrodes, comprising:

• forming an electrode of a first conductivity type from a silicon layer of a silicon-on-insulator substrate so that the electrode of the first conductivity type is established at least on an insulator layer of the silicon-on-insulator substrate,
• the silicon layer having the first conductivity type;
• removing a portion of the insulator layer so that at least a portion of a substrate surface of the substrate is exposed;
• establishing an epitaxial layer at least on the exposed portion,
• the epitaxial layer having a second conductivity type,
• whereby the epitaxial layer of the second conductivity type forms an electrode of the second conductivity type at least on the insulator layer and on the exposed portion of the substrate
• so that the electrode of the second conductivity type is electrically connected to the substrate,
• the electrode of the second conductivity type being electrically isolated from the electrode of the first conductivity type through the substrate via the insulator layer,
• wherein the first conductivity type is different than the second conductivity type and
• wherein the electrode of the first conductivity type has a vertical sidewall facing a vertical sidewall of the electrode of the second conductivity type,
• whereby a gap is located between the two vertical sidewalls;
• and
• forming the nanowire such that it extends laterally between the two vertical sidewalls, the nanowire including:
• at least one segment of a first material and of the first conductivity type;
• at least one segment of a second material and of the second conductivity type,
• the second material being different from the first material;
• and
• a heterojunction formed between the segments.

A method for forming a device having a nanowire and at least one junction formed laterally between two electrodes, comprising:

• establishing an insulator layer on a substrate so that a first portion of a substrate surface remains exposed;
• establishing an epitaxial layer of a first conductivity type at least on the exposed first portion, thereby forming an electrode of the first conductivity type at least on the insulator layer;
• removing a portion of the epitaxial layer of the first conductivity type, thereby re- exposing the first portion and leaving at least a portion of the epitaxial layer of the first conductivity type on at least a portion of the insulator layer adjacent to the re-exposed first portion;
• establishing an epitaxial layer of a second conductivity type at least on the re-exposed first portion,
• whereby the epitaxial layer of the second conductivity type forms
• an electrode of the second conductivity type that is electrically isolated from the electrode of the first conductivity type through the substrate via the insulator layer and
• is established at least on the insulator layer and on the substrate so that the electrode of the second conductivity type is electrically connected to the substrate,
• wherein the first conductivity type is different than the second conductivity type and
• wherein the electrode of the first conductivity type has a vertical sidewall facing a vertical sidewall of the electrode of the second conductivity type,
• whereby a gap is located between the two vertical sidewalls;
• and
• forming a nanowire that extends laterally between the two vertical sidewalls,
• the nanowire including:
• at least one segment of a first material and of the first conductivity type;
• at least one segment of a second material and of the second conductivity type,
• the second material being different from the first material;
• and
• a heterojunction formed between the segments.