Nanowire varactor diode and methods of making same

A method of making a varactor diode, comprising:

• (a) depositing a semiconductor nanowire, having a first conductivity type, on a substrate, wherein said nanowire has a length and a diameter thereby defining an surface;
• (b) forming an insulator on at least a portion of the surface;
• (c) doping a region of the nanowire with a second conductivity type material;
• (d) forming a first electrical contact on at least part of the insulator and the doped region;
• and
• (e) forming a second electrical contact on the nanowire, wherein an inversion layer is formed at a region at the surface of the nanowire and a depletion region is formed within the nanowire upon application of a voltage between the first and second electrical contacts, such that the varactor diode exhibits variable capacitance as a function of the applied voltage.

A method of making a varactor diode, comprising:

• (a) depositing a semiconductor nanowire on a substrate, the nanowire having a first conductivity type core and an insulating shell;
• (b) doping a region of the nanowire with a second conductivity type material;
• (c) forming a first electrical contact on at least part of the insulator and the doped region;
• and
• (d) forming a second electrical contact on the nanowire, wherein an inversion layer is formed at a region at the surface of the nanowire and a depletion region is formed within the nanowire upon application of a voltage between the first and second electrical contacts, such that the varactor diode exhibits variable capacitance as a function of the applied voltage.

A method of making a varactor diode, comprising:

• (a) depositing a semiconductor nanowire on a substrate, the nanowire having a first conductivity type core, an insulating shell, and a conductor layer surrounding the shell;
• (b) doping a region of the nanowire with a second conductivity type material;
• (c) forming a first electrical contact on the conductor layer and the doped region;
• and
• (d) forming a second electrical contact on the nanowire, wherein an inversion layer is formed at a region at the surface of the nanowire and a depletion region is formed within the nanowire upon application of a voltage between the first and second electrical contacts, such that the varactor diode exhibits variable capacitance as a function of the applied voltage.

A varactor diode, comprising:

• a substrate;
• a semiconductor nanowire having a solid core, supported by said substrate, having a first conductivity type and having a region doped with a second conductivity type, wherein said nanowire has a length and a diameter thereby defining an surface;
• an insulator formed on at least a portion of said surface;
• a first electrical contact formed on at least part of said insulator and coupled to said doped region;
• and
• a second electrical contact coupled to said nanowire, wherein an inversion layer is formed at a region at the surface of said nanowire and a depletion region is formed within said nanowire upon application of a voltage between said first and second electrical contacts, such that the varactor diode exhibits variable capacitance as a function of the applied voltage.