# Tetramethylammonium hydroxide (TMAH) treatment of dry-etched trenches on (010) β-Ga2O3 to enhance trench profiles

https://mdr.nims.go.jp/datasets/9c8dc921-09a0-4a42-88e0-fb29825f89f7

## Files

- [article.pdf](https://mdr.nims.go.jp/filesets/8806845e-4442-4532-b9ae-aef929e77507/download) ([Detail](https://mdr.nims.go.jp/filesets/8806845e-4442-4532-b9ae-aef929e77507.md))

## Id

9c8dc921-09a0-4a42-88e0-fb29825f89f7

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-02-24T02:19:21.774506Z

## Updated at

2026-02-25T03:30:03.810696Z

## Published at

2026-02-25T01:40:30.313265Z

## Doi



## First published url

https://doi.org/10.1063/5.0305647

## Date published

2026-02-01

## Recorded date published

2026-2-1

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: Tetramethylammonium hydroxide (TMAH) treatment of dry-etched trenches on
    (010) β-Ga2O3 to enhance trench profiles
  title_type: original
  lang: en

## Description

- description: We demonstrated heated tetramethylammonium hydroxide (TMAH) etching
    (25 wt. % concentration, at 90 °C) as an effective post-dry-etch treatment for
    improving dry-etched trench profiles on (010) β-Ga2O3. This treatment successfully
    converted rough, tapered dry-etched trench sidewalls into smooth, vertical ones,
    except for trenches oriented close to the [201] direction, where side etching
    was most pronounced. In particular, when trenches were oriented along the [102]
    direction, the exposed vertical sidewalls became exceptionally flat, indicating
    the preferential development of (⁠-201) facets. At the same time, the initially
    convex trench bottoms were planarized, yielding a well-defined box-like cross-sectional
    profile. Importantly, both the (⁠-201) sidewalls and the (010) bottom surface
    underwent only minimal material removal, consistent with the very low etch rates
    of these crystallographic planes. Together with its known ability to alleviate
    dry-etch damage, TMAH etching can, therefore, be regarded as a highly effective
    post-treatment for dry-etched fins and trenches on the (010) plane.
  description_type: abstract
  lang: und

## Creator

- name: Takayoshi Oshima
  role: author
  orcid: https://orcid.org/0000-0001-8550-9735

## Contact agent



## Publisher

organization: AIP Publishing

## Managing organization



## Keyword

- subject: Ga2O3
  schema: not_defined
- subject: TMAH
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by/4.0/

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## Data origin



## Embargo



## Journal

- title: AIP Advances
  issn: '21583226'
  volume: '16'
  issue: '2'
  article_number: '025145'

## Conference



## Related item



## Funding

- identifier: JP24K01368
  funder_name: Japan Society for the Promotion of Science

## Instrument



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## Measurement method



## Specimen



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## Fileset

- id: 8806845e-4442-4532-b9ae-aef929e77507
  filename: article.pdf
  content_type: application/pdf
  size: 16772131
  md5: 9f6b83ab794387f2f9d7ff4951406b9c

## Thumbnail

fileset_id: 8806845e-4442-4532-b9ae-aef929e77507
filename: article.pdf