ScAlN etch mask for highly selective silicon etching

Henry, Michael David; Young, Travis R.; Griffin, Ben

doi:10.1116/1.4994841

Title: ScAlN etch mask for highly selective silicon etching

Abstract

Here, this work reports the utilization of a recently developed film, ScAlN, as a silicon etch mask offering significant improvements in high etch selectivity to silicon. Utilization of ScAlN as a fluorine chemistry based deep reactive ion etch mask demonstrated etch selectivity at 23 550:1, four times better than AlN, 11 times better than Al₂O₃, and 148 times better than silicon dioxide with significantly less resputtering at high bias voltage than either Al₂O₃ or AlN. Ellipsometry film thickness measurements show less than 0.3 nm/min mask erosion rates for ScAlN. Micromasking of resputtered Al for Al₂O₃, AlN, and ScAlN etch masks is also reported here, utilizing cross-sectional scanning electron microscope and confocal microscope roughness measurements. With lower etch bias, the reduced etch rate can be optimized to achieve a trench bottom surface roughness that is comparable to SiO₂ etch masks. Etch mask selectivity enabled by ScAlN is likely to make significant improvements in microelectromechanical systems, wafer level packaging, and plasma dicing of silicon.

Authors:

Henry, Michael David ^[1]; Young, Travis R. ^[1]; Griffin, Ben ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Fri Sep 08 00:00:00 EDT 2017

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1406366

Alternate Identifier(s):: OSTI ID: 1380046

Report Number(s):: SAND-2017-11101J
Journal ID: ISSN 2166-2746; 657803

Grant/Contract Number:: AC04-94AL85000; 180906

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Vacuum Science and Technology B

Additional Journal Information:: Journal Volume: 35; Journal Issue: 5; Journal ID: ISSN 2166-2746

Publisher:: American Vacuum Society/AIP

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Henry, Michael David, Young, Travis R., and Griffin, Ben. ScAlN etch mask for highly selective silicon etching.  United States: N. p., 2017. 
Web.  doi:10.1116/1.4994841.

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                    Henry, Michael David, Young, Travis R., & Griffin, Ben. ScAlN etch mask for highly selective silicon etching.  United States.  https://doi.org/10.1116/1.4994841

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                    Henry, Michael David, Young, Travis R., and Griffin, Ben. Fri .  
"ScAlN etch mask for highly selective silicon etching".  United States.  https://doi.org/10.1116/1.4994841.  https://www.osti.gov/servlets/purl/1406366.

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@article{osti_1406366,

  title        = {ScAlN etch mask for highly selective silicon etching},

  author       = {Henry, Michael David and Young, Travis R. and Griffin, Ben},

  abstractNote = {Here, this work reports the utilization of a recently developed film, ScAlN, as a silicon etch mask offering significant improvements in high etch selectivity to silicon. Utilization of ScAlN as a fluorine chemistry based deep reactive ion etch mask demonstrated etch selectivity at 23 550:1, four times better than AlN, 11 times better than Al2O3, and 148 times better than silicon dioxide with significantly less resputtering at high bias voltage than either Al2O3 or AlN. Ellipsometry film thickness measurements show less than 0.3 nm/min mask erosion rates for ScAlN. Micromasking of resputtered Al for Al2O3, AlN, and ScAlN etch masks is also reported here, utilizing cross-sectional scanning electron microscope and confocal microscope roughness measurements. With lower etch bias, the reduced etch rate can be optimized to achieve a trench bottom surface roughness that is comparable to SiO2 etch masks. Etch mask selectivity enabled by ScAlN is likely to make significant improvements in microelectromechanical systems, wafer level packaging, and plasma dicing of silicon.},

  doi          = {10.1116/1.4994841},

  journal      = {Journal of Vacuum Science and Technology B},

  number       = 5,

  volume       = 35,

  place        = {United States},

  year         = {Fri Sep 08 00:00:00 EDT 2017},

  month        = {Fri Sep 08 00:00:00 EDT 2017}

}

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Works referencing / citing this record:

Review—Beyond the Highs and Lows: A Perspective on the Future of Dielectrics Research for Nanoelectronic Devices
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Title: ScAlN etch mask for highly selective silicon etching

Abstract

Citation Formats

Review—Beyond the Highs and Lows: A Perspective on the Future of Dielectrics Research for Nanoelectronic Devices journal, January 2019

Review—Beyond the Highs and Lows: A Perspective on the Future of Dielectrics Research for Nanoelectronic Devices
journal, January 2019