Thin film trnsistor, method for producing a thin film transistor and electronic device having such a transistor

A method for producing a thin film transistor on a substrate comprising a semiconductor layer having an undoped region in between a first doped region and a second doped region and an oxide layer partially covering a surface of the semiconductor layer, the oxide layer carrying a conductive gate over the undoped region, the conductive gate having a first side and a second side substantially perpendicular to the oxide layer;

• the first doped region and the second doped region having been formed in a self-alignment step using the conductive gate as a mask, the method comprising the steps of:
• providing a first spacer and a second spacer on the oxide layer adjacent to the first side and second side of the conductive gate respectively;
• implanting a first further doped region and a second further doped region into the semiconductor layer using the conductive gate, the first spacer and the second spacer as a further mask, the first further doped region and the second further doped region being more conductive than the first doped region and the second doped region;
• providing a first insulating spacer on the oxide layer adjacent to the first spacer opposite the first side of the conductive gate and a second insulating spacer on the oxide layer adjacent to the second spacer opposite the second side of the conductive gate;
• removing an exposed area of the oxide layer covering the first further doped region and the second further doped region;
• and
• providing the first further doped region with a first conductive contact and the second further doped region with a second conductive contact.