Tri-gate orthogonal channel transistor and methods of forming the same

A method of forming a semiconductor device, the method comprising:

• forming a drain region, a backside gate electrode, a backside gate dielectric layer, and a first source portion in an upper portion of an insulating matrix layer;
• forming a metal oxide semiconductor channel layer over the drain region, the backside gate dielectric, and the first source portion;
• forming a first gate electrode over a horizontal top surface of the metal oxide semiconductor channel layer;
• and
• forming a second gate electrode over a sidewall of the metal oxide semiconductor channel layer.

A method of forming a semiconductor device, the method comprising:

• forming a drain region, a backside gate electrode, a backside gate dielectric layer, and a first source portion in an upper portion of an insulating matrix layer;
• forming a metal oxide semiconductor channel layer over the drain region, the backside gate dielectric, and the first source portion;
• forming a second source portion by doping a portion of the metal oxide semiconductor channel layer or by replacing a portion of the metal oxide semiconductor channel layer with a conductive material portion, wherein the second portion of a source region contacts the first portion of the source region;
• and
• forming a first gate electrode over a horizontal top surface of the metal oxide semiconductor channel layer.