Abstract: Methods and apparatus for producing a thin film transistor (TFT) result in: a semiconductor layer; a channel region formed on or in the semiconductor layer and having first and second opposing ends, and having third and fourth opposing ends transverse to the first and second ends; an n-type source structure disposed on or in the semiconductor layer adjacent to the first end of the channel; an n-type drain structure disposed on or in the semiconductor layer adjacent to the second end of the channel; a p-type source structure disposed on or in the semiconductor layer adjacent to the third end of the channel; a p-type drain structure disposed on or in the semiconductor layer adjacent to the fourth end of the channel; and a gate structure disposed over the channel region.