Hybrid devices based on a heterojunction between inorganic and organic semiconductors have offered a means to combine the advantages of both classes of materials in optoelectronic devices, but, in practice, the performance of such devices has often been disappointing. Here, it is demonstrated that charge generation in hybrid inorganic–organic heterojunctions consisting of copper thiocyanate (CuSCN) and a variety of molecular acceptors (ITIC, IT‐4F, Y6, PC70BM, C70, C60) proceeds via emissive charge‐transfer (CT) states analogous to those found at all‐organic heterojunctions. Importantly, contrary to what has been observed at previous organic–inorganic heterojunctions, the dissociation of the CT‐exciton and subsequent charge separation is efficient, allowing the fabrication of planar photovoltaic devices with very low non‐radiative voltage losses (0.21 ±  0.02 V). It is shown that such low non‐radiative recombination enables the fabrication of simple and cost‐effective near‐IR (NIR) detectors with extremely low dark current (4 pA cm−2) and noise spectral density (3 fA Hz−1/2) at no external bias, leading to specific detectivities at NIR wavelengths of just under 1013 Jones, close to the performance of commercial silicon photodetectors. It is believed that this work demonstrates the possibility for hybrid heterojunctions to exploit the unique properties of both inorganic and organic semiconductors for high‐performance opto‐electronic devices.

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Thin film transistors (TFTs) can be used to determine the bulk‐like mobilities of amorphous semiconductors. Different amine‐based organic hole transporting materials (HTs) used in organic light‐emitting diodes have been investigated. In addition, the present study also measures the TFT hole mobilities of two iridium phosphors: Ir(ppy)3 and Ir(piq)3. These materials are grown separately on SiO2 and polystyrene (PS). On SiO2, the TFT mobilities are found to be 1–2 orders smaller than the bulk values obtained by time‐of‐flight (TOF) technique. On PS gate dielectric layer, the TFT mobilities are in good agreement TOF data. Only 10 nm of organic semiconductor is sufficient for TFTs to achieve TOF mobilities. Using the Gaussian disorder model, it is found that on SiO2 surface, when compared to the bulk values, the energetic disorders (s) of the HTs increase and simultaneously, the high temperature limits (µ∞) of the carrier mobilities decrease. Both s and µ∞ contribute to the reduction of the carrier mobility. The increase in s is related to the presence of randomly oriented polar Si‐O bonds. The reduction of µ∞ on SiO2 is related to the orientations of the more planar molecules which tend to lie horizontally on the surface.

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