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In this paper, we discuss some issues related to the design, implementation, and test of a CMOS active pixel sensor chip (RAPS01), developed in the framework of the radiation active pixel sensors (RAPS) INFN project. Two different basic pixel schemes have been proposed. The first one is based on a standard active pixel sensor (APS) architecture, while a second architecture, named weak inversion pixel sensor (WIPS) exploits a different circuitry which allows for 'sparse' access mode and thus for speeding-up the readout phase. Chip fabrication has been completed and a preliminary test phase has been performed. A suitable test environment has been devised and test strategies have been planned. Preliminary test results, featuring a static and dynamic characterization of the basic sensitive elements are outlined. Future works are also outlined, aimed at the optimization of a second version of the chip, more effectively integrating smart circuitry. Index Terms--Active pixel, CMOS, radiation sensor.

This paper aims at exploring and validating the adoption of standard fabrication processes for the realization of CMOS active pixel sensors, for particle detection purposes. The goal is to implement a single-chip, complete radiation sensor system, including on a CMOS integrated circuit the sensitive devices, read-out and signal processing circuits. A prototype chip (RAPS01) based on these principles has been already fabricated, and a chip characterization has been carried out; in particular, the evaluation of the sensitivity of the sensor response on the actual operating conditions was estimated, as well as the response uniformity. Optimization and tailoring of the sensor structures for High Energy Physics applications are being evaluated in the design of the next generation chip (RAPS02). Basic features of the new chip includes digitally configurable readout and multi-mode access (i.e., either sparse of line-scan readout). [ABSTRACT FROM AUTHOR]

Provides information on a study which examined the issue of numerical modeling of radiation-damaged silicon devices. Details on the solid-state semiconductor particle detectors; Information on the radiation damage modeling; Conclusion.

In this paper we discuss some design, implementation and test issues, with respect to the development of the RAPS01 chip in the framework of the Radiation Active Pixel Sensors (RAPS) INFN project. The project aimed at verifying feasibility of smart, high-resolution pixel arrays with a fully standard, submicron CMOS technology for particle detection purposes. Layout optimization of the pixel, including sensitive element and local read and amplification circuits has been carried out. Different basic pixel schemes and read-out options have been proposed and devised. Chip fabrication has been completed and test phase is now under way: to this purpose a suitable test environment has been devised and test strategies have been planned. [Copyright &y& Elsevier]

Device simulation allows for accurate analysis of device behavior, accounting for several physical details that cannot easily be taken into account within compact, equivalent-circuit models. This is especially true for some issues typical of the design of silicon radiation detectors, where silicon properties are exploited in a non-conventional way and radiation damage raises severe reliability concerns. In this paper, a couple of significant applications of device simulation to the investigation and design of advanced solid-state radiation sensors are presented. More specifically, (i) radiation damage influence on detectors operating at cryogenic temperatures is successfully modeled and (ii) features of an innovative scheme for CMOS active pixel sensors are analyzed by means of mixed-mode simulation tools. From these examples, the usefulness and potentiality of advanced simulation techniques in the perspective of radiation detectors can be appreciated. [Copyright &y& Elsevier]