New type of charged-particles detector based on point contacts formed in a GaAs-AlGaAs heterostructure by split-gates

We propose a new principle for a low temperature semiconductor detector of charged particles with possibly submicron lateral resolution based on point contacts formed in the 2-dimensional electron gas (2DEG) of a GaAs-AlxGa1-xAs heterostructure using split-gates. The detector operates up to liquid nitrogen temperatures.

Impinging particles excite locally extra donors in the doping layer of the heterostructure. By measuring simultaneous increase in the conductances of 3 point contacts due to the impacts of charged particles the position of penetration is calculated using the Thomas-Fermi approximation for screening in 2DEG.