Patterned backgating using single-sided mask aligners: application to density-matched electron-hole bilayers
arXiv:0807.0117 · doi:10.1063/1.3032942
Abstract
We report our work on fabricating lithographically aligned patterned backgates on thin (50-60m) \Roman{roman3}-\Roman{roman5} semiconductor samples using {\it single sided mask aligners only}. Along with this we also present a way to photograph both sides of a thin patterned chip using inexpensive infra-red light emitting diodes (LED) and an inexpensive (consumer) digital camera. A robust method of contacting both sides of a sample using an ultrasonic bonder is described. In addition we present a mathematical model to analyse the variation of the electrochemical potential through the doped layers and heterojunctions that are normally present in most GaAs based devices. We utilise the technique and the estimates from our model to fabricate an electron-hole bilayer device in which each layer is separately contacted and has tunable densities. The electron and hole layers are separated by barriers either 25 or 15nm wide. In both cases, the densities can be matched by using appropriate bias voltages.
7 pages, 8 EPS figures. Submitted to Journal of Applied Physics
References in corpus (7)
- Drag in paired electron-hole layers
- Correlation Effects on the Coupled Plasmon Modes of a Double Quantum Well
- Gate-Controlled Electron Spin Resonance in a GaAs/AlGaAs Heterostructure
- Undoped Electron-Hole Bilayers in a GaAs/AlGaAs Double Quantum Well
- Closely spaced and separately contacted 2d electron and 2d hole gases by in situ focussed ion implantation
- Transport and drag in undoped electron-hole bilayers
- Layer interdependence of transport in an undoped electron-hole bilayer