Extracting Mobility-Lifetime Product in Solar Cell Absorbers Using Quantum Efficiency Analysis. Issue 1771 (18th May 2015)

• Record Type: Journal Article
• Authors: Poindexter, Jeremy R.; Brandt, Riley E.; Mangan, Niall M.; Buonassisi, Tonio
• Editors: Gloeckler, M.; Tiwari, A.N.; Yamada, A.; Yan, Y.; Kim, J.Y.; Miyasaka, T.; Mora-Seró, I.; Zhu, K.; Andersson, M.; Manca, J.V.; Palomares, E.; Vandewal, K.; Li, T.; Mastro, M.; Tao, M.; Wang, Q.
• Is Part Of: MRS proceedings. Issue 1771(2015)
• Publication Date: 2015-05-18
• Subjects: thin film, -- photovoltaic, -- simulation; Electrical engineering -- Congresses; Physics -- Congresses; Materials -- Research -- Congresses; Materials science -- Congresses; 620.11
• DOI: 10.1557/opl.2015.483
• Languages: English
• ISSNs: 0272-9172

Abstract

ABSTRACT: The long-wavelength quantum efficiency (QE) response of photovoltaic absorbers is determined by the length scales for minority carrier collection. However, extracting quantitative measurements of minority carrier mobility-lifetime product ( μτ ) is complicated by uncertainty in other factors such as the depletion width, electric field, and the absorption coefficient. We apply previously developed methods to obtain estimates for μτ in a tin(II) sulfide (SnS) solar cell. We compare three analytic models for the minority carrier collection probability as a function of absorber depth to determine which model most accurately captures the behavior in our devices. For models in which multiple parameters are unconstrained, a random numerical search is used to optimize the fit to experimental QE for SnS. To identify sources of error, we perform a sensitivity analysis by fitting with SCAPS-1D. Our analysis shows that changes in absorption most strongly affect estimates for μτ, highlighting the need to obtain accurate, device-specific absorption data. Further modeling and experimental constraints are required to obtain self-consistent values for μτ that correspond to actual device performance.