Dr. Laurence Singleton Profile

Dr. Laurence Singleton

at Fraunhofer ICT-IMM

SPIE Involvement:

Author

Publications (6)

Proceedings Article | 28 May 2003 Paper

Mask technologies for deep x-ray LIGA

Laurence Singleton, Peter Detemple

Proceedings Volume 5148, (2003) https://doi.org/10.1117/12.515144

KEYWORDS: Photomasks, X-rays, Manufacturing, Silicon, X-ray lithography, Polymethylmethacrylate, X-ray technology, Gold, Beryllium, Lithography

Read Abstract +

Proceedings Article | 25 March 2003 Paper

Variants of LIGA technology for the production of plastic microcomponents

Laurence Singleton, Peter Detemple, Holger Loewe

Proceedings Volume 4945, (2003) https://doi.org/10.1117/12.468413

KEYWORDS: Photomasks, X-rays, X-ray lithography, Lithography, Gold, Silicon, Manufacturing, Ultraviolet radiation, Electron beam lithography, Synchrotron radiation

Read Abstract +

Proceedings Article | 17 January 2003 Paper

Plastic micro-optical components with LIGA technology

Laurence Singleton, Peter Detemple, I. Frese, Thomas Klotzbuecher, Hans-Dieter Bauer

Proceedings Volume 4984, (2003) https://doi.org/10.1117/12.499993

KEYWORDS: Photomasks, Waveguides, X-rays, Manufacturing, Polymers, Structured optical fibers, Lithography, X-ray lithography, Optical alignment, Polymethylmethacrylate

Read Abstract +

Proceedings Article | 24 July 2002 Paper

Design of experiments optimization of PMMA for LIGA applications

Laurence Singleton, Rainer Schenk, Oliver Haverbeck, Abdi Tunayer, Anja Himmelsbach, Christiana Krempel, Peter Detemple, Manfred Lachar

Proceedings Volume 4690, (2002) https://doi.org/10.1117/12.474195

KEYWORDS: Polymethylmethacrylate, X-ray lithography, X-rays, Photomasks, Polymers, Photoresist processing, Lithography, Synchrotron radiation, Oxides, Polymerization

Read Abstract +

Proceedings Article | 20 August 2001 Paper

Deep x-ray lithography with the SU-8 resist

Laurence Singleton, Alexei Bogdanov, Serguei Peredkov, Oliver Wilhelmi, Andreas Schneider, Carsten Cremers, Stephan Megtert, Andreas Schmidt

Proceedings Volume 4343, (2001) https://doi.org/10.1117/12.436647

KEYWORDS: Polymethylmethacrylate, Critical dimension metrology, X-rays, X-ray lithography, Aluminum, Synchrotrons, Scanning electron microscopy, Photomasks, Photons, Calibration

Read Abstract +

Although the process of deep x-ray lithography with PMMA achieves good resolution, it requires significant exposure times because of the low sensitivity of PMMA to x-rays. Therefore resist materials, which can achieve high resolution, but which are inherently more sensitive than PMMA, are desirable. Here it is shown, that x-ray exposures of the SU-8 resist can achieve high resolution with substantially reduced exposure times. Irradiation at the synchrotron source of DCI at Lure (Paris) and MAXLAB (Lund, Sweden) demonstrated a reduced exposure time for a 600 micrometers thick SU-8 relative to PMMA. The does needed to obtain standing structures was 30 J/Cm³ for DCI and 52 J/CM³ for MAXLAB. A 600 micrometers thick PMMA resist requires a typical bottom does of 4 kJ/cm³, so Su-8 is considerably more sensitive to x-rays than PMMA. Preliminary critical dimension measurements (CD) of the 600 micrometers SU-8 resist structures have been obtained for the entire height of the structure, which was exposed at DCI. The CD measurements were made in a Scanning Electron Microscope (SEM) using 10 micrometers wide structures, which have a 20micrometers pitch, this being used to calibrate the measurements. These measurements show that the gain in the critical dimension per structure edge is dependent on the bottom dose. Doses of 30 J/cm³ achieved a CD gain per edge of +0.5 micrometers , while doses of 40 J/cm³ Yielded a CD gain per edge of 0.9 micrometers . However, the gain in the CD per edge is critically dependent on the solvent content in the resist. Doses of 40 J/cm³ into a resist with a 2% residual solvent content yielded CD gains per edge of 0.3micrometers . In addition, the dose profile in the resist does not change the CD values significantly. It has been shown that the resolution of the x-ray exposed SU-8 structures compare quite favorable with PMMA, but the exposure time for SU-8 is approximately 100 times less than that for PMMA. This significantly improves throughput for deep x-ray lithography processes.

Proceedings Article | 18 August 2000 Paper

Miniaturized objective lens for a photoelectron emission microscope

Laurence Singleton, Yannick Ansel, Ralf Baron, Gebhard Marx, Matthias Nienhaus, Felix Schmitz, Gerd Schoenhense, Andreas Schmidt

Proceedings Volume 4179, (2000) https://doi.org/10.1117/12.395685

KEYWORDS: Electrodes, Objectives, Microscopes, Semiconducting wafers, Gold, Manufacturing, Scanning electron microscopy, Ceramics, X-rays, Control systems

Read Abstract +

Showing 5 of 6 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years