Facilities

The Centre for Graphene Science has access to an array of leading facilities at both the Exeter and Bath research sites.

At Bath we have significant fabrication facilites, which are located within the The David Bullett laboratory, and include photolithography, electron-beam lithography, thin-film deposition, surface characterisation and device packaging.

At Exeter we have recently completed installation of a new cleanroom facility.

Cleanroom

The Graphene Centre Cleanroom is a purpose built semiconductor type cleanroom with advanced air-conditioning control of temperature and humidity throughout the working areas. Incoming air is filtered to provide ISO Class 5 and 6 working environments. It has a swipe-card entry system ensuring secure access into the facility. One acid and two solvent benches with their own air extract systems are built into the facility to complement the fabrication processes. The rooms will be completed by the beginning of March 2011 and it is hope that all equipment will be installed and commissioned by the end of April 2011.

An existing optical lithography system and a critical point dryer will be relocated into the area and ancillary equipment such as optical microscopes, a wire bonding tool, a room temperature wafer probe station, a surface profiler, a split tube annealing furnace and a dicing saw will be incorporated to make this, as much as possible, a self-contained installation. Significant equipment purchases for the facility are as follows:

NanoBeam Electron Beam Lithography System

A state-of-the-art dedicated electron beam lithography tool capable of producing 10nm lines (±15%) across a 250um Field using a 2nA Beam. Each of the fields can be accurately positioned and joined together using a 195mm x 195mm precision stage controlled by a 0.31nm (l/2048) laser interferometer system. It has a 20 bit, 55Mhz pattern generator with 1nm resolution (beam-step) at a 1mm field size. The NanoBeam system is capable of directly writing on a variety of samples ranging from 5mm to 150mm square which would allow us to fabricate optical mask plates in addition to doing direct write lithography on small samples. It has a 10 chuck automatic airlock which allows unattended operation over night or at weekends.

KJL Evaporation System

A custom designed Combined Electron Beam and Sputtering Evaporation System with substrate RF DC biasing and the capacity to oxidise samples during the deposition process. It has a 10kW Ebeam power supply which means it is capable of evaporating a wide range of materials. It has a 3” diameter sputtering target for enhanced deposition uniformity and automatic operation using a recipe driven computer control system.

RIE Etching System

An automatic computer controlled Reactive Ion Etching system fitted with a Laser Etch Penetration Depth (EPD) monitoring system to accurately control etch depths. It has the facility to use six different process gases so is very versatile and can easily be adapted for future research work.