Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing

K. Torrance, H.E. Keenan

Research output: Contribution to conferencePaper

Abstract

The toxicology of gallium arsenide is well established; it is classified by the state of California as a known carcinogen. Consequently, environmental aspects of GaAs wafer manufacture are coming under greater scrutiny, with the cost of waste disposal becoming an economic issue for fabs operating under this jurisdiction. It is estimated that 85% of a GaAs boule is lost during manufacturing and device packaging, which usually ends up land filled as hazardous waste. This percentage is likely to increase as final wafer thickness is reduced to improve thermal dissipation. GaAs wafer backthinning and polishing generates waste slurries that are contaminated by arsenic and must be disposed of as hazardous waste. Although GaAs is largely insoluble in H2O, it is readily oxidized to soluble oxides and hydroxides, especially during chemo-mechanical polishing. Further, the valency state of the arsenic species determines the toxicity of effluent. Waste slurries from three sources were studied by ICP-MS and ICP-OES analysis to determine the amount of arsenic in the supernate and the form of the arsenic species. This data was related to mechanical lapping processes, such as the size distribution of particles in the slurry, and to the oxidation chemistry of the polishing processes. The analytical results provide guidance as to the most effective strategy to minimize the environmental impact of slurries produced during wafer thinning and polishing.

Conference

Conference2009 International Conference on Compound Semiconductor MANufacturing TECHnology
CityTampa, Florida, USA
Period18/05/0921/05/09

Fingerprint

gallium
arsenic
hazardous waste
toxicology
carcinogen
waste disposal
slurry
hydroxide
thinning
dissipation
environmental impact
manufacturing
oxide
effluent
toxicity
economics
cost

Keywords

  • gallium arsenide
  • lapping
  • waste slurry
  • toxicology
  • ICP-MS
  • ICP-OES

Cite this

Torrance, K., & Keenan, H. E. (2009). Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing. Paper presented at 2009 International Conference on Compound Semiconductor MANufacturing TECHnology, Tampa, Florida, USA, .
Torrance, K. ; Keenan, H.E. / Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing. Paper presented at 2009 International Conference on Compound Semiconductor MANufacturing TECHnology, Tampa, Florida, USA, .
@conference{f2a8bee870e24ef8b51c9363a7e9950b,
title = "Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing",
abstract = "The toxicology of gallium arsenide is well established; it is classified by the state of California as a known carcinogen. Consequently, environmental aspects of GaAs wafer manufacture are coming under greater scrutiny, with the cost of waste disposal becoming an economic issue for fabs operating under this jurisdiction. It is estimated that 85{\%} of a GaAs boule is lost during manufacturing and device packaging, which usually ends up land filled as hazardous waste. This percentage is likely to increase as final wafer thickness is reduced to improve thermal dissipation. GaAs wafer backthinning and polishing generates waste slurries that are contaminated by arsenic and must be disposed of as hazardous waste. Although GaAs is largely insoluble in H2O, it is readily oxidized to soluble oxides and hydroxides, especially during chemo-mechanical polishing. Further, the valency state of the arsenic species determines the toxicity of effluent. Waste slurries from three sources were studied by ICP-MS and ICP-OES analysis to determine the amount of arsenic in the supernate and the form of the arsenic species. This data was related to mechanical lapping processes, such as the size distribution of particles in the slurry, and to the oxidation chemistry of the polishing processes. The analytical results provide guidance as to the most effective strategy to minimize the environmental impact of slurries produced during wafer thinning and polishing.",
keywords = "gallium arsenide, lapping, waste slurry, toxicology, ICP-MS, ICP-OES",
author = "K. Torrance and H.E. Keenan",
year = "2009",
month = "5",
day = "20",
language = "English",
note = "2009 International Conference on Compound Semiconductor MANufacturing TECHnology ; Conference date: 18-05-2009 Through 21-05-2009",

}

Torrance, K & Keenan, HE 2009, 'Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing' Paper presented at 2009 International Conference on Compound Semiconductor MANufacturing TECHnology, Tampa, Florida, USA, 18/05/09 - 21/05/09, .

Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing. / Torrance, K.; Keenan, H.E.

2009. Paper presented at 2009 International Conference on Compound Semiconductor MANufacturing TECHnology, Tampa, Florida, USA, .

Research output: Contribution to conferencePaper

TY - CONF

T1 - Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing

AU - Torrance, K.

AU - Keenan, H.E.

PY - 2009/5/20

Y1 - 2009/5/20

N2 - The toxicology of gallium arsenide is well established; it is classified by the state of California as a known carcinogen. Consequently, environmental aspects of GaAs wafer manufacture are coming under greater scrutiny, with the cost of waste disposal becoming an economic issue for fabs operating under this jurisdiction. It is estimated that 85% of a GaAs boule is lost during manufacturing and device packaging, which usually ends up land filled as hazardous waste. This percentage is likely to increase as final wafer thickness is reduced to improve thermal dissipation. GaAs wafer backthinning and polishing generates waste slurries that are contaminated by arsenic and must be disposed of as hazardous waste. Although GaAs is largely insoluble in H2O, it is readily oxidized to soluble oxides and hydroxides, especially during chemo-mechanical polishing. Further, the valency state of the arsenic species determines the toxicity of effluent. Waste slurries from three sources were studied by ICP-MS and ICP-OES analysis to determine the amount of arsenic in the supernate and the form of the arsenic species. This data was related to mechanical lapping processes, such as the size distribution of particles in the slurry, and to the oxidation chemistry of the polishing processes. The analytical results provide guidance as to the most effective strategy to minimize the environmental impact of slurries produced during wafer thinning and polishing.

AB - The toxicology of gallium arsenide is well established; it is classified by the state of California as a known carcinogen. Consequently, environmental aspects of GaAs wafer manufacture are coming under greater scrutiny, with the cost of waste disposal becoming an economic issue for fabs operating under this jurisdiction. It is estimated that 85% of a GaAs boule is lost during manufacturing and device packaging, which usually ends up land filled as hazardous waste. This percentage is likely to increase as final wafer thickness is reduced to improve thermal dissipation. GaAs wafer backthinning and polishing generates waste slurries that are contaminated by arsenic and must be disposed of as hazardous waste. Although GaAs is largely insoluble in H2O, it is readily oxidized to soluble oxides and hydroxides, especially during chemo-mechanical polishing. Further, the valency state of the arsenic species determines the toxicity of effluent. Waste slurries from three sources were studied by ICP-MS and ICP-OES analysis to determine the amount of arsenic in the supernate and the form of the arsenic species. This data was related to mechanical lapping processes, such as the size distribution of particles in the slurry, and to the oxidation chemistry of the polishing processes. The analytical results provide guidance as to the most effective strategy to minimize the environmental impact of slurries produced during wafer thinning and polishing.

KW - gallium arsenide

KW - lapping

KW - waste slurry

KW - toxicology

KW - ICP-MS

KW - ICP-OES

UR - http://www.csmantech.org

M3 - Paper

ER -

Torrance K, Keenan HE. Characterization of arsenic-rich waste slurries generated during gallium arsenide wafer lapping and polishing. 2009. Paper presented at 2009 International Conference on Compound Semiconductor MANufacturing TECHnology, Tampa, Florida, USA, .