Case study of failure analysis in thin film silicon solar cell

Article history: Received 25 May 2015 Received in revised form 20 June 2015 Accepted 21 June 2015 Available online xxxx Thin-film siliconmodules are commonly produced by an alternating sequence of layer deposition and layer patterning steps, which lead to amonolithic series connected device. Most used process is laser scribing process that offers a high throughput and a small area loss. Tin oxide (SnO2) or zinc oxide (ZnO) are themost used front contact TCO in the superstrate configuration. ZnO presents better optical properties with respect to SnO2 and can be realized by low thermal and cost effective deposition processes. Electrical performance of our tandem thin film silicon cell deposited on ZnO front contact has shown higher shunt with respect with our reference process using SnO2 front contact, not explained only as difference between the twomaterials. In this work, a failure analysis process was followed in order to explain the origin of the difference. SEM, FIB and Auger electron spectroscopywere used in order to characterize the laser scribe that is known to be a possible cause of electrical deviation. We found residuals either on the bottom either on the later wall of P3 scribe that can explain the lowering shunt resistance and open circuit voltage observed into the electrical performances of the module. © 2015 Elsevier Ltd. All rights reserved.