A silicon position-sensitive detector of charged particles and radiations on the basis of functionally integrated structures with nano-micron active regions

Abstract

A novel pixel array two-coordinate detector with internal amplification is described. Linear amplification of the primary ionization current is attained by using functionally integrated structures of a p-i-n diode and a bipolar transistor in the detector pixel. It is shown that a 16-fold decrease (from 0.64 to 0.04 μm2) in the emitter area of the functionally integrated structures allows the current gain of pixel bipolar structures to be increased from 10 to 80 at a pixel collector current of ∼1 nA. As a result, it is possible to obtain spectra of radiations weakly interacting with the silicon (e.g., γ rays) and to reduce the response time of the position-sensitive detectors by an order of magnitude, down to 100 ns and less. It is demonstrated that the detector can be used in fast position-sensitive detection of particles with time, coordinate, and energy resolutions of ≤100 ns, ≤25 μm, and ≤12%, respectively.