We report on processing of p‐type bottom gate microcrystalline silicon thin film transistors (p‐type BG TFT). In particular, we demonstrate that a thermal annealing at 250 °C is required to get ideal contacts, regardless of the drain‐source met al. We found that aluminium is the best suited metal for source and drain contacts, as in the case of n‐type thin film transistors.The TFTs mobility and sub‐threshold slope (V/dec) are improved when a hydrogen plasma treatment was applied to the a‐SiN:H prior to µc‐Si deposition. Our best p‐type BG TFTs exhibit a field effect mobility of ∼ 1.2 cm2/Vs, a sub threshold slope of ∼1V/dec and an ON/OFF ratio of 105 while keeping a stable threshold voltage (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)