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Abstract Organic photodiodes (OPDs) offer a myriad of advantages over conventional inorganic photodetectors, making them particularly attractive for imaging application. One of the key challenges preventing their utilization is the need for their integration into the standard CMOS processing. Herein, we report a CMOS-compatible top-illuminated inverted small molecule bi-layer OPD with extremely low dark leakage current. The device utilizes a titanium nitride (TiN) bottom electrode modified by a [6,6]-phenyl C 61 butyric acid methyl ester (PCBM) cathode buffer layer (CBL). We systemetically show that doping the CBL enhances device's low voltage (below 1 V reverse bias) photoresponse by increasing the linear dynamic range (LDR) and making the bandwidth of the photodidoe broader without compromising the leakage current. The optimized device exhibits a dark leakage current of only ∼6 × 10−10 A/cm2 at −0.5 V. The external quantum efficiency (EQE) at 500 nm reaches 23% with a calculated specific detectivity as high as 7.15 × 1012 cm Hz1/2/W (Jones). Also the LDR approaches 140 dB and the bandwidth is about 400 kHz, at −0.5 V bias. The proposed device structure is fully compatible with CMOS processing and can be integrated onto a CMOS readout circuit offering the potential to be applied in high-performance large-scale imaging arrays. Graphical abstract Image 1 Highlights • Addressed constrains: 1) Low drive voltage (below |1| V), 2) TiN as opaque bottom electrode. 3) TiN is the cathode. • At below |1| V injection and collection efficiency are correlated. • At −0.5 V the bandwidth is 388 kHz, the detectivity is 7.15 × 1012 cm Hz1/2/W and the linear dynamic range (LDR) is 140 dB. • Thin bi-layer with dark leakage of only ∼6 × 10−10 A/cm2 at −0.5 V (BHJ, of similar thickness, shows higher leakage). • Towards integration with CMOS we report device stability and robustness to fabrication steps essential for such integration. [ABSTRACT FROM AUTHOR]