EU PVSEC Programme Online
EU PVSEC 2021, 6 - 10 September 2021
Presentation: 2DO.10.5 Electron Paramagentic Resonance Investigation of Mechanism of Light- and Elevated-Temperature-Induced Degradation in Ga-Doped Cz Si
Type: Oral
Date: Thursday, 9th September 2021
17:00 - 18:30
Author(s): A.R. Meyer, P.C. Taylor, V. LaSalvia, W. Nemeth, M. Page, D.L. Young, P. Stradins, S. Agarwal
Presenter / Speaker: A.R. Meyer, Colorado School of Mines, Golden, USA
Event: Conference Conference
Session: 2DO.10 Defects in Silicon and their Characterisation
Topic: 2. 1 Feedstock, Crystallisation, Wafering, Defect Engineering
Summary / Abstract: We report on the electron paramagnetic resonance (EPR) spectra recorded at 6 K for Ga-doped Czochralski (Cz) Si in the initial stages of light- and elevated-temperature-induced degradation (LeTID). We observe the LeTID effect in Ga-doped Cz Si samples; it has two characteristic EPR signatures (g12.000, which has not been identified, and g2=2.0055, which characterizes a Si dangling bond) that increase with exposure time, and then again decrease with further exposure as the carrier lifetime in the sample starts to regenerate. Additionally, we observe changes in the broad magnetic field spectra, which characterize the fine structure of the frozen out Ga acceptors. These changes mimic narrow magnetic field scans: its amplitude decreases as the minority carrier lifetime decreases and when the Ga-doped Cz Si sample starts to regenerate, the minority carrier lifetime increases and the fine structure increases. We postulate that LeTID is a result of extended H defects, such as platelets, which are formed upon firing and reconfigure to form Si dangling bonds at the platelet surface at low temperature during LeTID.