TY - JOUR
T1 - Soft photomask lithography and droplet spreading nano-imprinting for manufacturing patterned sapphire substrates
AU - Tu, Pei Chi
AU - Lee, Yung Chun
N1 - Funding Information:
This research was funded by the Ministry of Science and Technology of Taiwan under Project No. of MOST-108-2622-E-006-016-CC2. The authors are grateful for the technical and equipment support provided by the Center for Micro/Nano Science and Technology at National Cheng Kung University (Taiwan).
Funding Information:
This research was funded by the Ministry of Science and Technology of Taiwan under Project No. of MOST-108-2622-E-006-016-CC2 . The authors are grateful for the technical and equipment support provided by the Center for Micro/Nano Science and Technology at National Cheng Kung University (Taiwan).
Publisher Copyright:
© 2021 Elsevier B.V.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/3/15
Y1 - 2021/3/15
N2 - This paper proposes an innovative method for fabricating soft photomasks which can be used for contact type of photolithography. It utilizes a droplet spreading nano-imprinting technology to imprint a droplet of carbon-black photoresist (PR) on top of a glass substrate with a soft polydimethylsiloxane (PDMS) mold which contains patterned surface micro-cavities. By proper surface treatments on both surfaces of the PDMS mold and the glass substrate, it is possible to reversely fill the carbon-black resist into the surface micro-cavities of the mold and therefore result in a soft PDMS photomask. The experimental investigation is carried out with the application on photolithographic patterning on a 4″ sapphire substrate to achieve hexagonally arrayed PR micro-pillars with a feature size of around 1 to 2 μm. The soft PDMS photomask embedded with carbon-black resist is successfully produced. Excellent photolithography patterning results are also achieved on the 4″ sapphire wafer, which demonstrates the potential for manufacturing patterned sapphire substrates in the light-emitting-diode (LED) industry. Further developments and other possible applications of the proposed soft photomask lithography will be addressed.
AB - This paper proposes an innovative method for fabricating soft photomasks which can be used for contact type of photolithography. It utilizes a droplet spreading nano-imprinting technology to imprint a droplet of carbon-black photoresist (PR) on top of a glass substrate with a soft polydimethylsiloxane (PDMS) mold which contains patterned surface micro-cavities. By proper surface treatments on both surfaces of the PDMS mold and the glass substrate, it is possible to reversely fill the carbon-black resist into the surface micro-cavities of the mold and therefore result in a soft PDMS photomask. The experimental investigation is carried out with the application on photolithographic patterning on a 4″ sapphire substrate to achieve hexagonally arrayed PR micro-pillars with a feature size of around 1 to 2 μm. The soft PDMS photomask embedded with carbon-black resist is successfully produced. Excellent photolithography patterning results are also achieved on the 4″ sapphire wafer, which demonstrates the potential for manufacturing patterned sapphire substrates in the light-emitting-diode (LED) industry. Further developments and other possible applications of the proposed soft photomask lithography will be addressed.
UR - http://www.scopus.com/inward/record.url?scp=85102410974&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85102410974&partnerID=8YFLogxK
U2 - 10.1016/j.mee.2021.111528
DO - 10.1016/j.mee.2021.111528
M3 - Article
AN - SCOPUS:85102410974
SN - 0167-9317
VL - 241
JO - Microelectronic Engineering
JF - Microelectronic Engineering
M1 - 111528
ER -