A thin film transistor (TFT) to control a light emitting diode (LED) or an organic light emitting diode (OLED) includes a channel region configured as a saddle channel extending between the drain region and the source region of the TFT. The saddle channel is formed by deposition of channel material on a fin structure, and the contour of the saddle channel is defined by the contour of the fin structure. Deposition of the channel material for the saddle channel may be performed by: (i) atomic layer deposition (ALD) of amorphous silicon; (ii) ALD of amorphous silicon followed by annealing to form polycrystalline silicon; or (iii) deposition of indium gallium zinc oxide (IGZO) material by one of ALD, plasma-enhanced atomic layer deposition (PEALD), chemical vapor deposition (CVD), or plasma-enhanced chemical vapor deposition (PECVD).