Commissioning of new Electron Beam Lithography System

28 May 2009 – For immediate release.

The Department of Electronic Engineering is pleased to announce the general availability of a new  electron beam lithography (EBL) system for academic and non-academic use  in the Micro and Nano Fabrication Laboratory at The Chinese University of Hong Kong.  The machine was funded by  a one-off UGC Special Equipment Grant  awarded to a team led by Prof H.K.Tsang in August 2008.  During the tender exercise for the purchase of the equipment we asked leading EBL vendors from Japan and Europe to write  specially designed nanoscale patterns which tested the capability of the various EBL systems to produce ultrafine lines, long smooth line, precise grating period control, speed of writing, writing uniformity and stability, proximity effects and stitching errors.  After careful scanning electron microscope (SEM) inspection of the 4” test wafers submitted by four different vendors in the tender exercise, we selected the Elionix 7800 EBL system because of its overall performance.  Key factors in the selection of this vendor were the demonstrated capability of the system to keep stitching errors to under 30nm, the grating writing capability, comprehensive service support package and its highly competitive total costs. 

In the acceptance tests conducted on the machine installed at CUHK, the Elionix ELS7800 surpassed all specification requirements stipulated in the tender exercise.  The Elionix ELS7800 can write wafers up to 150mm in diameter and can write nanometer scale patterns within variable field sizes of up to 1.2mm.  The machine installed in CUHK can produce lines as small as 8nm (see photographs) on standard PMMA resist.  The Elionix ELS7800 system is a state of the art system for R&D and provides an enormous upgrade in the nanofabrication capability in Hong Kong. The system will be used for direct write patterning of nanometre scale patterns on semiconductor wafers.   The  nanotechnology research enabled by this instrument will have a important potential applications in a multitude of areas including optical communications, photovoltaics, biomedical sensing, and precision engineering.  Prof. H.K. Tsang’s research work on silicon photonics will benefit directly from this instrument because the machine now makes it possible for devices with sub-wavelength optical gratings, photonic crystals, chirped gratings and sub-micron sized silicon waveguides to be fabricated in Hong Kong. These nanoscale structures will be useful for next generation optical interconnects, silicon based photonic sensors and next generation optical communication  systems.

For further enquires, please contact Prof. Hon Tsang at hktsang@ee.cuhk.edu.hk