ELECTRICAL AND PHOTOELECTRIC PROPERTIES OF ORGANIC-INORGANIC HETEROJUNCTIONS PEDOT:PSS/n-CdTe

PEDOT: PSS thin films are widely used as transparent coatings in flexible semiconductor devices including solar cells. However, they are not widely used as transparent coatings in combination with crystal substrates. This work shows the possibility of using PEDOT:PSS thin films as a frontal transparent conducting layer in hybrid organic-inorganic Schottky type heterojunctions of the PEDOT:PSS/n-CdTe, which were prepared by deposition of PEDOT:PSS thin films (using the spin-coating method) on crystalline cadmium telluride substrates. The current-voltage (in a wide temperature range) and capacitance-voltage (at room temperature) characteristics of heterojunctions were measurement and analyzed. It has been established that PEDOT:PSS/n-CdTe heterojunctions have good diode properties with a high rectification ratio RR approximate to 10(5), a potential barrier height phi(0) = 0.95 eV, and series R-s = 91 Ohm and shunt R-sh = 5.7 x 10(7) Ohm resistances. Analysis of the forward branches of the I-V characteristics of heterojunctions showed that the dominant charge transfer mechanisms are determined by the processes of radiative recombination at low biases (3kT/e < V <0.3 V) and tunneling through a thin depleted layer at high biases (0.3 V <v <0.6= v). capacity-voltage characteristics are plotted in the mottschottky coordinate, taking into account influence of series resistance, measured at a frequency 1 mhz. used c-v characteristic was determined value built-in potential v(c) = 1.32 v (it correlates well with cutoff voltage from current-voltage characteristics) and concentration uncompensated donors n-CdTe substrate N-D-N-A = 8.79 x 10(14) cm(-3). although photoelectric parameters unoptimized pedot:pss heterojunctions low, their photodiode (detectivity D* > 10(13 )Jones) are very promising for further detailed analysis and improvement. The proposed concept of a hybrid organic-inorganic heterojunction also has potential for use in inexpensive gamma-and X-ray detectors.