Large Area Survey Grain Size and Texture Optimization For Thin Film CdTe Solar Cells Using Xenon-Plasma Focused Ion Beam (PFIB)

Vladislav Kornienko, Ochai Oklobia, Stuart Irvine, Steve Jones, Giray Kartopu, Ali Abbas, Yau Yau Tse, Jake Bowers, Kurt Barth, Michael Walls

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

2 Citations (Scopus)

Abstract

Microstructural analysis of high efficiency thin film CdTe solar cells has been obtained over large areas. Analysis regions are device cross-sections approximately 0.325 mm in length. The samples have been prepared using a xenon-plasma focused ion beam (Xe-PFIB). The detailed images of the microstructure were obtained using backscattered electron imaging and electron backscatter diffraction (EBSD). As deposited devices and those with a low level of cadmium chloride treatment both show strong (111) growth texture. A high density of twins is seen in the columnar grains. Three As doped FTO/CdZnS/CdTe with varying process conditions we devices with 13.1 %, 16.3% and 17% conversion efficiency were investigated. Lowest efficiency device was CdCl2 treated at 420°C for 10 minutes while the 16.3 and 17% devices were both treated at 440°C for 10 minutes. The large area analysis revealed a partial recrystallisation state in the 16.3% efficient device which was induced by an incomplete chloride activation process. The analysis confirms that the efficiency of the devices tends to correlate with grain size. It also showed that a strong correlation exists between device efficiency and the randomization of the texture away from the (111) grain orientation. EBSD can be used to survey large areas and to mark out features for more detailed analysis using transmission electron microscopy (TEM). As an example, we show how using an EBSD scanned cross-sectional area can identify a partially recrystallized region which is then extracted and analyzed in detail using TEM.

Original languageEnglish
Title of host publication2022 IEEE 49th Photovoltaics Specialists Conference, PVSC 2022
Place of PublicationPiscataway, NJ, USA
PublisherIEEE
Pages63-68
Number of pages6
ISBN (Electronic)9781728161174
DOIs
Publication statusPublished - 5 Jun 2022
Externally publishedYes
Event49th IEEE Photovoltaics Specialists Conference, PVSC 2022 - Philadelphia, United States
Duration: 5 Jun 202210 Jun 2022

Publication series

NameConference Record of the IEEE Photovoltaic Specialists Conference
Volume2022-June
ISSN (Print)0160-8371

Conference

Conference49th IEEE Photovoltaics Specialists Conference, PVSC 2022
Country/TerritoryUnited States
CityPhiladelphia
Period5/06/2210/06/22

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