Fig. 1. Y6-1O organic semiconductor materials and characterization：（a） Y6-1O atomic structure with high conjugation；（b） Polarization optical microscope image of Y6-1O single crystal（scale： 20 μm），the arrows indicate the polarization of the incident and collected light；（c） Field emission scanning electron microscopy（SEM） images of Y6-1O organic transistors；（d） Atomic force microscopy（AFM） images of Y6-1O organic transistors；（e） Thickness profile of Y6-1O organic materials and their corresponding optical images；（f） photoluminescence（PL） spectral properties of Y6-1O crystals with 1 060 nm，660 nm and 106 nm thickness

Fig. 2. Electrical and photoresponse of Y6-1O phototransistor with thickness of 106 nm：（a） Output characteristic curve at different bias gate voltages；（b） Transfer characteristic curves under different drain-source voltages；（c） Transfer characteristic curves at different power densities of 638 nm，V_ds = 40 V；（d） Schematic diagram of photoresponse band of Y6-1O crystal；（e） Photoresponse of Y6-1O transistor at different power densities of incident light at 638 nm and 405 nm，V_ds = 40 V；（f） The photocurrent of 638 nm and 405 nm irradiation as a function of the incident light power.

Fig. 3. Photoresponse of Y6-1O under different gate voltages：（a-c） The photoresponses for light from 400 nm to 1 000 nm under different gate voltages of 40 V（a），0 V（b），and -40 V（c），when P = 10 mW/cm² and V_ds = 40 V；（d-f） Schematic of the band diagrams under gate voltage of 40 V（d），0 V（e），and -40 V（f）.（g） The spectral response of the Y6-1O phototransistor at different gate voltages.

Fig. 4. Photoresponse of Y6-1O with thickness of 660 nm：（a） Photoresponse of the device for light from 400 nm to 1 000 nm，when V_ds = 40 V，V_bg = 0 V；（b）（i）The photocurrent and power density relationship for different wavelengths.（b）（ii） The photo responsivity and power density relationship for different wavelengths.（c）The spectral response of Y6-1O phototransistors for different thicknesses（108 nm，660 nm） when P=10 mW/cm²