Simulation and measurements of charge collection in monolithic active pixel sensors

Citation
G. Deptuch et al., Simulation and measurements of charge collection in monolithic active pixel sensors, NUCL INST A, 465(1), 2001, pp. 92-100
Citations number
6
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement
Journal title
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
ISSN journal
0168-9002 → ACNP
Volume
465
Issue
1
Year of publication
2001
Pages
92 - 100
Database
ISI
SICI code
0168-9002(20010601)465:1<92:SAMOCC>2.0.ZU;2-4
Abstract
A preliminary study of the charge collection in the recently proposed Monol ithic Active Pixel Sensor devices for minimum ionising particles tracking i s presented. The baseline pixel architecture is similar to a visible light CMOS camera, emerged as a competitor to widespread CCDs. Free electrons cre ated by an impinging particle are collected by a photodiode from a thin par tially depleted epitaxial silicon layer allowing 100% of fill-factor. Such a structure is fabricated using standard CMOS process. The sensor and assoc iated readout electronics are integrated onto the same wafer. resulting in a low cost. high resolution and possibly thin detector. The crucial points of a CMOS detector are the time and the efficiency of the charge collection . These factors, in spite of undeniable advantages of CMOS detectors, can l imit their performances. The detailed 3-D simulations using commercially av ailable ISE-TCAD package are carried out in order to study a charge collect ion process. Although it is dominated by thermal diffusion, more than 1000 electrons are collected in the 3 x 3 pixels cluster within a time of 100 ns in a 15 mum thick epitaxial layer. Simulation results are compared to meas urements performed on the prototype APS CMOS MIMOSA using either a fast Inf rared (IR) laser or a high-energy particle beam as an excitation source. (C ) 2001 Elsevier Science B.V. All rights reserved.