Measurement of hole mobility in P3HT based photovoltaic cell using space charge limited current method

Mobility of carriers is one of the pivotal parameters characterizing any semiconducting material and it is important for organic semiconductors too. The mobility of organic semiconductors remains far less when compared to inorganic counterparts and hence attempts in the direction improvise it carries tremendous significance. This paper investigates the positive charge carriers transport properties in a bulk heterojunction organic photovoltaic cell using two different Anode Buffer Layers (PEDOT:PSS and MoO3). The method of Space Charge Limited Current (SCLC) is used to compute the hole mobilities and also the values are compared. The values obtained with PEDOT:PSS and MoO3 as HTLs are 1.043x10−4 cm2 V−1S−1 and 1.357x10−4 cm2V−1S−1 respectively. It is seen that the device with higher carrier mobility exhibits better performance.