Chemical method for producing smooth surfaces on silicon wafers

Title: Chemical method for producing smooth surfaces on silicon wafers

Abstract

An improved method for producing optically smooth surfaces in silicon wafers during wet chemical etching involves a pre-treatment rinse of the wafers before etching and a post-etching rinse. The pre-treatment with an organic solvent provides a well-wetted surface that ensures uniform mass transfer during etching, which results in optically smooth surfaces. The post-etching treatment with an acetic acid solution stops the etching instantly, preventing any uneven etching that leads to surface roughness. This method can be used to etch silicon surfaces to a depth of 200 .mu.m or more, while the finished surfaces have a surface roughness of only 15-50 .ANG. (RMS).

Inventors:

Yu, Conrad ^[1]

Antioch, CA

Issue Date:: 2003-01-01

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

OSTI Identifier:: 875025

Patent Number(s):: 6514875

Assignee:: The Regents of the University of California (Oakland, CA)

Patent Classifications (CPCs):: H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01L - SEMICONDUCTOR DEVICES

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H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01L - SEMICONDUCTOR DEVICES
H01L21/30608 - {Anisotropic liquid etching
H01L21/02019 - {Chemical etching}

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DOE Contract Number:: W-7405-ENG-48

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: chemical; method; producing; smooth; surfaces; silicon; wafers; improved; optically; wet; etching; involves; pre-treatment; rinse; post-etching; organic; solvent; provides; well-wetted; surface; ensures; uniform; mass; transfer; results; treatment; acetic; acid; solution; stops; instantly; preventing; uneven; leads; roughness; etch; depth; 200; mum; finished; 15-50; ang; rms; organic solvent; acid solution; smooth surface; wet chemical; producing optical; chemical method; /438/134/

Citation Formats


                    Yu, Conrad. Chemical method for producing smooth surfaces on silicon wafers.  United States: N. p., 2003. 
        Web.

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                    Yu, Conrad. Chemical method for producing smooth surfaces on silicon wafers.  United States.

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                    Yu, Conrad. Wed .  
        "Chemical method for producing smooth surfaces on silicon wafers".  United States.  https://www.osti.gov/servlets/purl/875025.

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@article{osti_875025,

  title        = {Chemical method for producing smooth surfaces on silicon wafers},

  author       = {Yu, Conrad},

  abstractNote = {An improved method for producing optically smooth surfaces in silicon wafers during wet chemical etching involves a pre-treatment rinse of the wafers before etching and a post-etching rinse. The pre-treatment with an organic solvent provides a well-wetted surface that ensures uniform mass transfer during etching, which results in optically smooth surfaces. The post-etching treatment with an acetic acid solution stops the etching instantly, preventing any uneven etching that leads to surface roughness. This method can be used to etch silicon surfaces to a depth of 200 .mu.m or more, while the finished surfaces have a surface roughness of only 15-50 .ANG. (RMS).},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2003},

  month        = {1}

}

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Works referenced in this record:

Etching roughness for (100) silicon surfaces in aqueous KOH
journal, September 1991

Palik, E. D.; Glembocki, O. J.; Heard, I.
Journal of Applied Physics, Vol. 70, Issue 6
https://doi.org/10.1063/1.349263

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Similar Records

Title: Chemical method for producing smooth surfaces on silicon wafers

Abstract

Citation Formats

Etching roughness for (100) silicon surfaces in aqueous KOH journal, September 1991

Etching roughness for (100) silicon surfaces in aqueous KOH
journal, September 1991