Enhancement of solar cell efficiency using laser texturing

number: 
693
إنجليزية
Degree: 
Author: 
Malak Salih Hussain Al-Qazzaz
Supervisor: 
Dr. Hassan W. Hilou
year: 
2002
Abstract:

In this work, laser texturing to enhance the efficiency of solar cell has been performed. The laser system used in this project is Nd-glass laser with wavelength of 1.06 urn, pulse energy of 0.4 to 1.2 J, pulse duration of (300 ms) and power density of 4.7x104 to 1.17x 107 W/cm2. The wafer surface has been textured as a mesh with spot diameter equal to 30 um and depth of 10 urn. The average efficiency of the laser texturing solar cell was calculated to be 12.9%. This is compared, with the untextured surface, which is having efficiency of 10.6%. The current-voltage characteristics were measured (0.4v, 31.5mA for untextured solar .cell and o.55v, 42 mA for the textured solar cell). The capacitance- voltage and the sheet resistivity were measured by using the (four-probe) device. It has been found that the losses of top grid of the local solar cell |; are too large. A new design has been proposed to decrease the losses. This design is based on using square wafer. The new design will decrease the power loss about 50%.