Solar cell carrier lifetimemeasurement

• Main Author: Li, Kun Peng.
• Other Authors: Sun Xiaowei
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/46548
• Institution: Nanyang Technological University

This final year project mainly focus on both investigating and developing the capabilities of infrared camera-based characterization techniques feasible for measuring the carrier lifetime of crystalline silicon solar cell material. First of all, the infrared lifetime mapping (ILM) technique is investigated, which was introduced as a fast and contact-free carrier lifetime imaging technique in the year 2000. It is based on the principle of absorption of infrared radiation by free carriers. The physical principles and necessary calibration procedures are discussed, the ILM provides the actual local lifetime at low-level injection, whereas many standard lifetime measurement techniques (e.g. MW-PCD) yield differential lifetimes only. Secondly, by using the infrared camera to measure the carrier lifetime of silicon solar cell, it significantly reduces the measurement times from hours to minutes or even seconds, where the laterally resolved information can be obtained without scanning the sample. In order to capture meaningful results on materials used in production environment, the use of blackbody and a suitable illumination source is critical. Thirdly, the quantitative comparison with other existing lifetime measurement approaches and applications to silicon samples at different process stages will be discussed. Finally, methods for further reducing the time of measurement with a greater degree are discussed, which may well be suitable for in-line process control in the sense of future implementation.