Dissolution of Oxygen Precipitate Nuclei in n-Type CZ-Si Wafers to Improve Their Material Quality: Experimental Results

Teh Tan; Ajay Upadhyaya; Keith Tate; Ajeet Rohatgi; Han Xu

doi:10.1109/JPHOTOV.2016.2621345

Dissolution of Oxygen Precipitate Nuclei in n-Type CZ-Si Wafers to Improve Their Material Quality: Experimental Results

Teh Tan, Ajay Upadhyaya, Keith Tate, Ajeet Rohatgi, Han Xu

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

13 Scopus Citations

Abstract

We present experimental results which show that oxygen-related precipitate nuclei (OPN) present in p-doped, n-type, Czochralski wafers can be dissolved using a flash-annealing process, yielding very high quality wafers for high-efficiency solar cells. Flash annealing consists of heating a wafer in an optical furnace to temperature between 1150 and 1250 degrees C for a short time. This process produces a large increase in the minority carrier lifetime (MCLT) and homogenizes each wafer. We have tested wafers from different axial locations of two ingots. All wafers reach nearly the same high value of MCLT. The OPN dissolution is confirmed by oxygen analysis using Fourier transform infrared spectra and injection-level dependence of MCLT.

Original language	American English
Pages (from-to)	97-103
Number of pages	7
Journal	IEEE Journal of Photovoltaics
Volume	7
Issue number	1
DOIs	https://doi.org/10.1109/JPHOTOV.2016.2621345
State	Published - 2017

NREL Publication Number

NREL/JA-5J00-66519

Keywords

charge carrier lifetime
chemical etching
optical furnace
silicon solar cells
spatial diversity

Access to Document

10.1109/JPHOTOV.2016.2621345

Cite this

@article{ee2b52c2a0314c37a79797e50615b08c,

title = "Dissolution of Oxygen Precipitate Nuclei in n-Type CZ-Si Wafers to Improve Their Material Quality: Experimental Results",

abstract = "We present experimental results which show that oxygen-related precipitate nuclei (OPN) present in p-doped, n-type, Czochralski wafers can be dissolved using a flash-annealing process, yielding very high quality wafers for high-efficiency solar cells. Flash annealing consists of heating a wafer in an optical furnace to temperature between 1150 and 1250 degrees C for a short time. This process produces a large increase in the minority carrier lifetime (MCLT) and homogenizes each wafer. We have tested wafers from different axial locations of two ingots. All wafers reach nearly the same high value of MCLT. The OPN dissolution is confirmed by oxygen analysis using Fourier transform infrared spectra and injection-level dependence of MCLT.",

keywords = "charge carrier lifetime, chemical etching, optical furnace, silicon solar cells, spatial diversity",

author = "Teh Tan and Ajay Upadhyaya and Keith Tate and Ajeet Rohatgi and Han Xu",

year = "2017",

doi = "10.1109/JPHOTOV.2016.2621345",

language = "American English",

volume = "7",

pages = "97--103",

journal = "IEEE Journal of Photovoltaics",

issn = "2156-3381",

publisher = "IEEE Electron Devices Society",

number = "1",

}

TY - JOUR

T1 - Dissolution of Oxygen Precipitate Nuclei in n-Type CZ-Si Wafers to Improve Their Material Quality: Experimental Results

AU - Tan, Teh

AU - Upadhyaya, Ajay

AU - Tate, Keith

AU - Rohatgi, Ajeet

AU - Xu, Han

PY - 2017

Y1 - 2017

N2 - We present experimental results which show that oxygen-related precipitate nuclei (OPN) present in p-doped, n-type, Czochralski wafers can be dissolved using a flash-annealing process, yielding very high quality wafers for high-efficiency solar cells. Flash annealing consists of heating a wafer in an optical furnace to temperature between 1150 and 1250 degrees C for a short time. This process produces a large increase in the minority carrier lifetime (MCLT) and homogenizes each wafer. We have tested wafers from different axial locations of two ingots. All wafers reach nearly the same high value of MCLT. The OPN dissolution is confirmed by oxygen analysis using Fourier transform infrared spectra and injection-level dependence of MCLT.

AB - We present experimental results which show that oxygen-related precipitate nuclei (OPN) present in p-doped, n-type, Czochralski wafers can be dissolved using a flash-annealing process, yielding very high quality wafers for high-efficiency solar cells. Flash annealing consists of heating a wafer in an optical furnace to temperature between 1150 and 1250 degrees C for a short time. This process produces a large increase in the minority carrier lifetime (MCLT) and homogenizes each wafer. We have tested wafers from different axial locations of two ingots. All wafers reach nearly the same high value of MCLT. The OPN dissolution is confirmed by oxygen analysis using Fourier transform infrared spectra and injection-level dependence of MCLT.

KW - charge carrier lifetime

KW - chemical etching

KW - optical furnace

KW - silicon solar cells

KW - spatial diversity

U2 - 10.1109/JPHOTOV.2016.2621345

DO - 10.1109/JPHOTOV.2016.2621345

M3 - Article

SN - 2156-3381

VL - 7

SP - 97

EP - 103

JO - IEEE Journal of Photovoltaics

JF - IEEE Journal of Photovoltaics

IS - 1

ER -

Dissolution of Oxygen Precipitate Nuclei in n-Type CZ-Si Wafers to Improve Their Material Quality: Experimental Results

Abstract

NREL Publication Number

Keywords

Access to Document

Fingerprint

Cite this