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)

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.

Copy to clipboard


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

Copy to clipboard


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

Copy to clipboard


                    
@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}

}

Copy to clipboard

Patent:

View Patent

Save / Share:

Export Metadata

Save to My Library

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
DOI: 10.1063/1.349263

Similar Records in DOE Patents and OSTI.GOV collections:

Method for producing smooth inner surfaces

Patent Cooper, Charles A.

The invention provides a method for preparing superconducting cavities, the method comprising causing polishing media to tumble by centrifugal barrel polishing within the cavities for a time sufficient to attain a surface smoothness of less than 15 nm root mean square roughness over approximately a 1 mm.sup.2 scan area. The method also provides for a method for preparing superconducting cavities, the method comprising causing polishing media bound to a carrier to tumble within the cavities. The method also provides for a method for preparing superconducting cavities, the method comprising causing polishing media in a slurry to tumble within the cavities.
Full Text Available
Wet-chemical systems and methods for producing black silicon substrates

Patent Yost, Vernon; Yuan, Hao-Chih; Page, Matthew

A wet-chemical method of producing a black silicon substrate. The method comprising soaking single crystalline silicon wafers in a predetermined volume of a diluted inorganic compound solution. The substrate is combined with an etchant solution that forms a uniform noble metal nanoparticle induced Black Etch of the silicon wafer, resulting in a nanoparticle that is kinetically stabilized. The method comprising combining with an etchant solution having equal volumes acetonitrile/acetic acid:hydrofluoric acid:hydrogen peroxide.
Full Text Available
Method for making circular tubular channels with two silicon wafers

Patent Yu, Conrad M [Antioch, CA]; Hui, Wing C [Campbell, CA]

A two-wafer microcapillary structure is fabricated by depositing boron nitride (BN) or silicon nitride (Si.sub.3 N.sub.4) on two separate silicon wafers (e.g., crystal-plane silicon with [100] or [110] crystal orientation). Photolithography is used with a photoresist to create exposed areas in the deposition for plasma etching. A slit entry through to the silicon is created along the path desired for the ultimate microcapillary. Acetone is used to remove the photoresist. An isotropic etch, e.g., such as HF/HNO.sub.3 /CH.sub.3 COOH, then erodes away the silicon through the trench opening in the deposition layer. A channel with a half-circular cross section ismore »« less
Full Text Available
Electrochemical method for defect delineation in silicon-on-insulator wafers

Patent Guilinger, Terry R [Albuquerque, NM]; Jones, Howland D. T. [Albuquerque, NM]; Kelly, Michael J [Albuquerque, NM]; ...

An electrochemical method for defect delineation in thin-film SOI or SOS wafers in which a surface of a silicon wafer is electrically connected so as to control the voltage of the surface within a specified range, the silicon wafer is then contacted with an electrolyte, and, after removing the electrolyte, defects and metal contamination in the silicon wafer are identified.
Full Text Available
Method for protecting chip corners in wet chemical etching of wafers

Patent Hui, Wing C [Campbell, CA]

The present invention is a corner protection mask design that protects chip corners from undercutting during anisotropic etching of wafers. The corner protection masks abut the chip corner point and extend laterally from segments along one or both corner sides of the corner point, forming lateral extensions. The protection mask then extends from the lateral extensions, parallel to the direction of the corner side of the chip and parallel to scribe lines, thus conserving wafer space. Unmasked bomb regions strategically formed in the protection mask facilitate the break-up of the protection mask during etching. Corner protection masks are useful formore »« less
Full Text Available

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