Front-End Performance and Charge Collection Properties of Heavily Irradiated DNW MAPS

Dipt. di Elettron., Univ. degli Studi di Pavia, Pavia, Italy
IEEE Transactions on Nuclear Science (Impact Factor: 1.28). 09/2010; 57(4):1781 - 1789. DOI: 10.1109/TNS.2009.2039003
Source: IEEE Xplore


Deep N-well (DNW) CMOS monolithic active pixel sensors (MAPS) fabricated in a 130 nm technology have been exposed to γ-rays up to an integrated dose of about 10 Mrad and subjected to a 100 °C/168 h annealing cycle. Device tolerance to total ionizing dose has been evaluated by monitoring the change in charge sensitivity, noise and charge collection properties after each step of the irradiation and annealing campaign. Damage mechanisms and their relation to front-end architecture and sensor features are thoroughly discussed by comparing the response to ionizing radiation of different test structures and based on radiation induced degradation models in single MOS transistors.

Download full-text


Available from: F. Morsani,
  • Source
    • "In the sensing electrode only the charge that is generated in a relatively small region of the substrate in an epitaxial layer with a typical thickness of about 12 µm. Measurements on previous prototypes show that the average charge signal in a single pixel for a MIP is expected to be around 1000 electrons [4]. This sets the system constraints in terms of charge sensitivity and noise performance. "
    [Show abstract] [Hide abstract]
    ABSTRACT: This work is concerned with the design of two different analog channels for hybrid and monolithic pixels readout in view of applications to the SuperB vertex detector. The circuits have been designed in a 130 nm, vertically integrated CMOS technology, which may provide advantages in terms of functional density and electrical isolation between the analog and the digital sections of the front-end. The paper discusses the main features of the two channels, with emphasis on some specific problems and their solution through purposely devised blocks and suitable design criteria. An evaluation of the technology will be also provided through characterization of the prototypes produced within the first 3D multiproject run with Tezzaron/Globalfoundries.
    10/2011; DOI:10.1109/NSSMIC.2011.6153983
  • [Show abstract] [Hide abstract]
    ABSTRACT: The SuperB asymmetric e+ e− collider has been designed to deliver a luminosity greater than 1036 cm−2 s−1 maintaining moderate beam currents. Comparing to current B-Factories, the reduced center-of-mass boost of the SuperB machine requires an improved vertex resolution to allow precision measurements sensitive to New Physics. Therefore the SuperB Silicon Vertex Tracker will be equipped with an innermost Layer0 with a radius of about 1.5 cm, high granularity, low material budget and able to withstand a background rate of several MHz/cm2. We report on the status of the R&D on the different options under study for the Layer0: DNW MAPS, hybrid pixels and thin pixels developed with vertical integration technology.
    Nuclear Science Symposium Conference Record (NSS/MIC), 2010 IEEE; 01/2010
  • [Show abstract] [Hide abstract]
    ABSTRACT: Monolithic active pixel sensors in CMOS technology, featuring a deep N-well as the collecting electrode (so called DNW MAPS), have been exposed to neutrons from a nuclear reactor, up to a total 1 MeV neutron equivalent fluence of about 3.7×1013 cm−2. The irradiation campaign was aimed at studying the effects of radiation induced displacement damage on the charge collection properties of the device, which was conceived for applications to charged particle tracking in high energy physics experiments. A number of different techniques, including electrical characterization of the front-end electronics and of DNW diodes, laser stimulation of the sensors and tests with 55Fe and 90Sr radioactive sources, has been employed for evaluating the device operation before and after irradiation. This paper discusses the measurement results and their relation with the bulk damage mechanisms underlying performance degradation in DNW MAPS.
    IEEE Transactions on Nuclear Science 01/2011; 59(4):297-304. DOI:10.1109/RADECS.2011.6131308 · 1.28 Impact Factor
Show more