Effect of chemical treatments on nm-scale electrical characteristics of polycrystalline thin film Cu(In,Ga)Se2 surfaces

Wenjie Li; Sidney R. Cohen; David Cahen

doi:10.1016/j.solmat.2013.09.030

Effect of chemical treatments on nm-scale electrical characteristics of polycrystalline thin film Cu(In,Ga)Se₂ surfaces

Wenjie Li, Sidney R. Cohen, David Cahen

Weizmann Institute of Science

Research output: Contribution to journal › Article › peer-review

25 Scopus citations

Abstract

Conducting Probe AFM. CP-AFM, was used to follow how chemical etching, oxidation, and sulfurization affect the surface nanoscale electrical characteristics of polycrystalline Cu(In,Ga)Se₂ (CIGS) thin films. Band bending at grain boundaries (GBs) on the surface was studied and analyzed by CP-AFM - measured photocurrents. We find that both oxidation and sulfurization can passivate the GBs of the CIGS films; oxidation increases n-type band bending, which impedes the transport of photogenerated electrons, while sulfurization increases p-type band bending at GBs, which helps this transport. Differences in effects between surface terminations by sulfide, selenide and oxide were analyzed. The effects of these treatments on the electrical activity of the GBs of the films, as well as the importance of the use of chemical bath deposition of the CdS buffer, are explained within a defect surface chemistry model.

Original language	English
Pages (from-to)	500-505
Number of pages	6
Journal	Solar Energy Materials and Solar Cells
Volume	120
Issue number	PART B
DOIs	https://doi.org/10.1016/j.solmat.2013.09.030
State	Published - Jan 2014
Externally published	Yes

Funding

We thank J.F. Guillemoles (IRDEP, Chatou, France) and Gary Hodes (Weizmann) for many discussions and valuable input on the topic over many years. We thank Th. Rissom for sample growth, T. Münchenberg, C. Kelch and M. Kirsch for technical support, and D. Abou-Ras and S. Sadewasser (all from Helmholtz- Zentrum Berlin) and K. Gartsman (Weizmann) for helpful discussions. This work was supported in part by the Wolfson Trust , the Helmsley Trust , the Nancy and Stephen Grand Center for Sensors and Security and the GMJ Schmidt Minerva Centre for Supramolecular architecture (collaboration with Helmholtz Inst.). DC holds the Sylvia and Rowland Schaefer Chair in Energy Research.

Funders	Funder number
Nancy and Stephen Grand Center for Sensors and Security
Leona M. and Harry B. Helmsley Charitable Trust
Wolfson Family Charitable Trust

Keywords

Oxidation
Selenization
Solar cells
Sulfurization
Surface treatment

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1016/j.solmat.2013.09.030

Cite this

@article{80995d2356df4eb89032f3dc26bd8def,

title = "Effect of chemical treatments on nm-scale electrical characteristics of polycrystalline thin film Cu(In,Ga)Se2 surfaces",

abstract = "Conducting Probe AFM. CP-AFM, was used to follow how chemical etching, oxidation, and sulfurization affect the surface nanoscale electrical characteristics of polycrystalline Cu(In,Ga)Se2 (CIGS) thin films. Band bending at grain boundaries (GBs) on the surface was studied and analyzed by CP-AFM - measured photocurrents. We find that both oxidation and sulfurization can passivate the GBs of the CIGS films; oxidation increases n-type band bending, which impedes the transport of photogenerated electrons, while sulfurization increases p-type band bending at GBs, which helps this transport. Differences in effects between surface terminations by sulfide, selenide and oxide were analyzed. The effects of these treatments on the electrical activity of the GBs of the films, as well as the importance of the use of chemical bath deposition of the CdS buffer, are explained within a defect surface chemistry model.",

keywords = "Oxidation, Selenization, Solar cells, Sulfurization, Surface treatment",

author = "Wenjie Li and Cohen, {Sidney R.} and David Cahen",

year = "2014",

month = jan,

doi = "10.1016/j.solmat.2013.09.030",

language = "אנגלית",

volume = "120",

pages = "500--505",

journal = "Solar Energy Materials and Solar Cells",

issn = "0927-0248",

publisher = "Elsevier B.V.",

number = "PART B",

}

TY - JOUR

T1 - Effect of chemical treatments on nm-scale electrical characteristics of polycrystalline thin film Cu(In,Ga)Se2 surfaces

AU - Li, Wenjie

AU - Cohen, Sidney R.

AU - Cahen, David

PY - 2014/1

Y1 - 2014/1

N2 - Conducting Probe AFM. CP-AFM, was used to follow how chemical etching, oxidation, and sulfurization affect the surface nanoscale electrical characteristics of polycrystalline Cu(In,Ga)Se2 (CIGS) thin films. Band bending at grain boundaries (GBs) on the surface was studied and analyzed by CP-AFM - measured photocurrents. We find that both oxidation and sulfurization can passivate the GBs of the CIGS films; oxidation increases n-type band bending, which impedes the transport of photogenerated electrons, while sulfurization increases p-type band bending at GBs, which helps this transport. Differences in effects between surface terminations by sulfide, selenide and oxide were analyzed. The effects of these treatments on the electrical activity of the GBs of the films, as well as the importance of the use of chemical bath deposition of the CdS buffer, are explained within a defect surface chemistry model.

AB - Conducting Probe AFM. CP-AFM, was used to follow how chemical etching, oxidation, and sulfurization affect the surface nanoscale electrical characteristics of polycrystalline Cu(In,Ga)Se2 (CIGS) thin films. Band bending at grain boundaries (GBs) on the surface was studied and analyzed by CP-AFM - measured photocurrents. We find that both oxidation and sulfurization can passivate the GBs of the CIGS films; oxidation increases n-type band bending, which impedes the transport of photogenerated electrons, while sulfurization increases p-type band bending at GBs, which helps this transport. Differences in effects between surface terminations by sulfide, selenide and oxide were analyzed. The effects of these treatments on the electrical activity of the GBs of the films, as well as the importance of the use of chemical bath deposition of the CdS buffer, are explained within a defect surface chemistry model.

KW - Oxidation

KW - Selenization

KW - Solar cells

KW - Sulfurization

KW - Surface treatment

UR - http://www.scopus.com/inward/record.url?scp=84889079511&partnerID=8YFLogxK

U2 - 10.1016/j.solmat.2013.09.030

DO - 10.1016/j.solmat.2013.09.030

M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???

AN - SCOPUS:84889079511

SN - 0927-0248

VL - 120

SP - 500

EP - 505

JO - Solar Energy Materials and Solar Cells

JF - Solar Energy Materials and Solar Cells

IS - PART B

ER -