[ Best Paper of This Month ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 29, No. 4, pp.267-273

ISSN: 2508-5107 (Online)

Print publication date 15 Aug 2020

Received 31 Mar 2020 Revised 09 Jun 2020 Accepted 19 Jun 2020

DOI: https://doi.org/10.7735/ksmte.2020.29.4.267

대면적 레이저 직접묘화 공정에서 비점수차 자동초점 기술 연구

김기홍^a^{, *} ; 최기봉^a

Astigmatic Autofocus for Large Area Direct Laser Writing

Geehong Kim^a^{, *} ; Keebong Choi^a

aNano-Convergence Systems Research Division, Korea Institute Machinery and Materials

Correspondence to: ^*Tel.: +82-42-868-7076 E-mail address: geehong@kimm.re.kr (Geehong Kim).

Abstract

We developed an astigmatic autofocus optics and a control unit which were implemented in a direct laser writing system for a large area patterning process. The autofocus module is comprised of a collimated laser, a quadrant photodiode, an astigmatic lens, and a few polarizing optics. This system has a 0.526 V/μm focus error signal resolution in the 50x objective lens and a surface tracking capability of under 1 mm/s XY translation stage speed. In this study, we conducted a patterning experiment using SU-8 photocurable resist on a silicon wafer to study the accuracy of the astigmatic autofocus system. We highlighted some features of this system for future improvement.

Keywords:

Autofocus, Astigmatism, Direct laser writing, 3D patterning

Acknowledgments

이 논문은 산업통산자원부의 재원으로 한국산업기술진흥원의 지원을 받아 수행된 산업기술혁신사업입니다(N0002310).

References

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Geehong Kim

Senior Researcher in the Nano-Convergence Systems Research Division, Korea Institute of Machinery and Materials.His research interest is 3D structure fabrication in nano and micro scale using two-photon polymerization.

E-mail: geehong@kimm.re.kr

Keebong Choi

Senior Researcher in the Nano-Convergence Systems Research Division, Korea Institute of Machinery and Materials.His research interest is the design and control of piezo-driven mechanism for ultra-precision motion .

E-mail: kbchoi@kimm.re.kr