Organic Photovoltaic Fabrication and Test Apparatus

Return to Research Tool Menu

Overview

It takes many trials to perfect the materials and techniques that make for highly efficient organic solar cells. This apparatus at University of Arizona combines a vacuum fabrication area with a inert gas glove box where prototype cells can be tested under controlled circumstance.

The most common test is to generate a voltage vs current curve by experimentally varying the level of light used to excite the cell and by continually changing the load on the cell using a variable voltage power supply (reverse polarity). First a the cell is kept in the dark and a whole series of voltages are applied while the current is measured. Then this series of measurements is repeated while the cell is illuminated. Typical measurements open-circuit voltage (V_oc), short-circuit current (I_sc), fill factor (FF), maximum power output of the device (P_max), voltage at maximum power (V_max), current at maximum power (I_max). A higher Fill Factor means that the cells is operating closer to its theoretical maximum efficiency.

See wiki article on Physics_of_Solar_Cells

Operation

<swf width="600" height="500">http://depts.washington.edu/cmditr/media/opvfab.swf</swf>