Since the float-zone (FZ) silicon has lower contaminations and longer minority-carrier lifetime than those in Czochralski silicon and other semiconductor materials, it has potential advantages to fabricate bipolar detectors on the high-purity FZ silicon substrate to achieve a high gain at ultra-low-signal levels. The authors present preliminary experimental results on a bipolar detector fabricated on an unusual high-purity FZ silicon substrate. A backside gettering layer of phosphorus-doped polysilicon was employed to preserve the long carrier lifetime of the high-purity FZ silicon. The device has been investigated in the detection of a continuous flux of X-ray and infrared light. The bipolar detector with a circular emitter of 2 mm diameter has demonstrated high gains up to 3820 for 22 keV X-ray from a 1 mCi Cd radioactive source (the X-ray photon flux, received by the detector is estimated to be similar to7.77 x 10(4)/S). High gain up to 4400 for 0.17 nW light with a wavelength of 0.83 mum has been observed for the same device. (C) 2003 Elsevier B.V. All rights reserved.
|Autori:||Han DJ; Batignani G; Del Guerra A; Dalla Betta GF; Boscardin M; Bosisio L; Giorgi M; Forti F|
|Titolo:||High-gain bipolar detector on float-zone silicon|
|Anno del prodotto:||2003|
|Digital Object Identifier (DOI):||10.1016/S0168-9002(03)01947-8|
|Appare nelle tipologie:||1.1 Articolo in rivista|