High contrast 3D proximity correction for electron-beam lithography: An enabling technique for the fabrication of suspended masks for complete device fabrication within an UHV environment

Mark C. Rosamond, Joseph T. Batley, Gavin Burnell, Bryan J. Hickey, Edmund H. Linfield

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Many devices, such as lateral spin valves, depend critically on the quality of interfaces formed between different materials, and hence require the entire device to be fabricated within an ultra-high vacuum environment. This is possible using angled deposition with a suspended mask such that, by depositing from specific angles, different patterns form on the substrate beneath. We use a bi-layer of MMA(8.5)-MAA copolymer and PMMA patterned by electron-beam lithography (EBL) to form such a mask. It is necessary, though, to perform proximity effect correction (PEC) in EBL to achieve the correct spatial distribution of electrons, and hence produce the desired pattern in the developed resist. For bi-layer processes this is a three-dimensional (3D) correction since we must optimise for two different critical doses (one for the copolymer, the other for the PMMA) at defined 3D positions within the resist stack. We perform this 3D correction using the commercial software BEAMER produced by GenISys GmbH. We show that by applying manual shape segregation and modulation to the exposure pattern, prior to the "3DPEC" algorithm, it is possible to achieve much higher contrasts in the spatial distribution of absorbed energy and hence significantly increase the processing window, and yield in the fabrication of suspended masks.

Original languageEnglish (US)
Pages (from-to)5-10
Number of pages6
JournalMicroelectronic Engineering
Volume143
DOIs
StatePublished - Aug 1 2015

Fingerprint

Electron beam lithography
proximity
Masks
masks
lithography
Polymethyl Methacrylate
electron beams
Fabrication
Spatial distribution
fabrication
copolymers
spatial distribution
Copolymers
Ultrahigh vacuum
ultrahigh vacuum
Modulation
computer programs
modulation
dosage
Electrons

Keywords

  • 3D-PEC
  • Angled evaporation
  • E-beam lithography
  • GenISys beamer
  • Lateral spin valve
  • Suspended shadow mask

Cite this

High contrast 3D proximity correction for electron-beam lithography : An enabling technique for the fabrication of suspended masks for complete device fabrication within an UHV environment. / Rosamond, Mark C.; Batley, Joseph T.; Burnell, Gavin; Hickey, Bryan J.; Linfield, Edmund H.

In: Microelectronic Engineering, Vol. 143, 01.08.2015, p. 5-10.

Research output: Contribution to journalArticle

@article{e3fd1b25936149f78d1166fc5d1f735d,
title = "High contrast 3D proximity correction for electron-beam lithography: An enabling technique for the fabrication of suspended masks for complete device fabrication within an UHV environment",
abstract = "Many devices, such as lateral spin valves, depend critically on the quality of interfaces formed between different materials, and hence require the entire device to be fabricated within an ultra-high vacuum environment. This is possible using angled deposition with a suspended mask such that, by depositing from specific angles, different patterns form on the substrate beneath. We use a bi-layer of MMA(8.5)-MAA copolymer and PMMA patterned by electron-beam lithography (EBL) to form such a mask. It is necessary, though, to perform proximity effect correction (PEC) in EBL to achieve the correct spatial distribution of electrons, and hence produce the desired pattern in the developed resist. For bi-layer processes this is a three-dimensional (3D) correction since we must optimise for two different critical doses (one for the copolymer, the other for the PMMA) at defined 3D positions within the resist stack. We perform this 3D correction using the commercial software BEAMER produced by GenISys GmbH. We show that by applying manual shape segregation and modulation to the exposure pattern, prior to the {"}3DPEC{"} algorithm, it is possible to achieve much higher contrasts in the spatial distribution of absorbed energy and hence significantly increase the processing window, and yield in the fabrication of suspended masks.",
keywords = "3D-PEC, Angled evaporation, E-beam lithography, GenISys beamer, Lateral spin valve, Suspended shadow mask",
author = "Rosamond, {Mark C.} and Batley, {Joseph T.} and Gavin Burnell and Hickey, {Bryan J.} and Linfield, {Edmund H.}",
year = "2015",
month = "8",
day = "1",
doi = "10.1016/j.mee.2015.01.020",
language = "English (US)",
volume = "143",
pages = "5--10",
journal = "Microelectronic Engineering",
issn = "0167-9317",
publisher = "Elsevier",

}

TY - JOUR

T1 - High contrast 3D proximity correction for electron-beam lithography

T2 - An enabling technique for the fabrication of suspended masks for complete device fabrication within an UHV environment

AU - Rosamond, Mark C.

AU - Batley, Joseph T.

AU - Burnell, Gavin

AU - Hickey, Bryan J.

AU - Linfield, Edmund H.

PY - 2015/8/1

Y1 - 2015/8/1

N2 - Many devices, such as lateral spin valves, depend critically on the quality of interfaces formed between different materials, and hence require the entire device to be fabricated within an ultra-high vacuum environment. This is possible using angled deposition with a suspended mask such that, by depositing from specific angles, different patterns form on the substrate beneath. We use a bi-layer of MMA(8.5)-MAA copolymer and PMMA patterned by electron-beam lithography (EBL) to form such a mask. It is necessary, though, to perform proximity effect correction (PEC) in EBL to achieve the correct spatial distribution of electrons, and hence produce the desired pattern in the developed resist. For bi-layer processes this is a three-dimensional (3D) correction since we must optimise for two different critical doses (one for the copolymer, the other for the PMMA) at defined 3D positions within the resist stack. We perform this 3D correction using the commercial software BEAMER produced by GenISys GmbH. We show that by applying manual shape segregation and modulation to the exposure pattern, prior to the "3DPEC" algorithm, it is possible to achieve much higher contrasts in the spatial distribution of absorbed energy and hence significantly increase the processing window, and yield in the fabrication of suspended masks.

AB - Many devices, such as lateral spin valves, depend critically on the quality of interfaces formed between different materials, and hence require the entire device to be fabricated within an ultra-high vacuum environment. This is possible using angled deposition with a suspended mask such that, by depositing from specific angles, different patterns form on the substrate beneath. We use a bi-layer of MMA(8.5)-MAA copolymer and PMMA patterned by electron-beam lithography (EBL) to form such a mask. It is necessary, though, to perform proximity effect correction (PEC) in EBL to achieve the correct spatial distribution of electrons, and hence produce the desired pattern in the developed resist. For bi-layer processes this is a three-dimensional (3D) correction since we must optimise for two different critical doses (one for the copolymer, the other for the PMMA) at defined 3D positions within the resist stack. We perform this 3D correction using the commercial software BEAMER produced by GenISys GmbH. We show that by applying manual shape segregation and modulation to the exposure pattern, prior to the "3DPEC" algorithm, it is possible to achieve much higher contrasts in the spatial distribution of absorbed energy and hence significantly increase the processing window, and yield in the fabrication of suspended masks.

KW - 3D-PEC

KW - Angled evaporation

KW - E-beam lithography

KW - GenISys beamer

KW - Lateral spin valve

KW - Suspended shadow mask

UR - http://www.scopus.com/inward/record.url?scp=84922156118&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84922156118&partnerID=8YFLogxK

U2 - 10.1016/j.mee.2015.01.020

DO - 10.1016/j.mee.2015.01.020

M3 - Article

AN - SCOPUS:84922156118

VL - 143

SP - 5

EP - 10

JO - Microelectronic Engineering

JF - Microelectronic Engineering

SN - 0167-9317

ER -