Possibility of Subelectron Noise With Room-Temperature Silicon Carbide Pixel Detectors

Pixel radiation detectors made on epitaxial silicon carbide are presented. Two small-format prototypes have been fabricated: a 4times4 matrix with pixels of 400times400 mum2 and 6times6 matrix with 200times200 mum2 pixels. Typical leakage currents between 3 fA and 10 fA for the larger pixel size, and between 0.1 fA and 4 fA for the small pixels have been measured at 27 degC, corresponding to current densities between 0.25 and 10 pA/cm2. In terms of equivalent noise charge, the contribution of most of the pixels is lower than 1 electron root mean square (rms) up to peaking times of tens of mus of pulse shaping. These pixel detectors are ready for applications in ultimate-resolution X-ray spectroscopic imaging at room temperature when a suitable ultra low noise front-end electronics, presently not available, will be developed. An analysis of the experimental data on these detectors coupled to front-end transistors of commercial CMOS technologies is presented, indicating that a noise level of around 4-electrons rms can be achieved at room temperature, limited by the front-end 1/f noise. The conditions to fully exploit the SiC pixel capabilities are quantitatively analysed by considering CMOS technologies for front-end and preamplifier design and the continuous progress in the SiC growing processes

[1]  H. Grubin.  The physics of semiconductor devices , 1979, IEEE Journal of Quantum Electronics.

[2]  A. Holland,et al.  Background rejection techniques in CCD X-ray detectors for astronomy , 1988 .

[3]  Marco Sampietro,et al.  Suboptimal filtering of 1/ƒ-noise in detector charge measurements , 1990 .

[4]  Marco Sampietro,et al.  Criteria for setting the width of CCD front end transistor to reach minimum pixel noise , 1996 .

[5]  Gregory Y. Prigozhin,et al.  Soft-X-ray CCD imagers for AXAF , 1997 .

[6]  Francesco Corsi,et al.  Ultra Low Noise CMOS preamplifier-shaper for X-ray spectroscopy , 1998 .

[7]  C. Davison,et al.  Simultaneous measurement of neutron and gamma-ray radiation levels from a TRIGA reactor core using silicon carbide semiconductor detectors , 1998 .

[8]  K. Hurley,et al.  Preliminary test results of pixel detectors developed for the All-sky X-ray and Gamma-ray Astronomy Monitor (AXGAM) , 1999, 1999 IEEE Nuclear Science Symposium. Conference Record. 1999 Nuclear Science Symposium and Medical Imaging Conference (Cat. No.99CH37019).

[9]  Aleksey E. Bolotnikov,et al.  High resolution CdZnTe pixel detectors with VLSI readout , 1999 .

[10]  G. Sato,et al.  High resolution CdTe detector and applications to imaging devices , 2000, 2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149).

[11]  P. Musico,et al.  The ATLAS silicon pixel sensors , 2001 .

[12]  B. Krieger,et al.  An 8/spl times/8 pixel IC for X-ray spectroscopy , 2001 .

[13]  Bradley,et al.  An 8x8 pixel array IC for X-ray spectroscopy , 2001 .

[14]  G. Deboy,et al.  Matched pair of CoolMOST/sup TM/ transistor with SiC-Schottky diode-advantages in application , 2001, Conference Record of the 2001 IEEE Industry Applications Conference. 36th IAS Annual Meeting (Cat. No.01CH37248).

[15]  A. Agarwal,et al.  SiC power-switching devices-the second electronics revolution? , 2002, Proc. IEEE.

[16]  D. P. Siddons,et al.  Development of a high-rate high-resolution detector for EXAFS experiments , 2002 .

[17]  Marcos Bavdaz,et al.  Hard X-ray test and evaluation of a prototype 32 32 pixel gallium-arsenide array , 2002 .

[18]  M. Trimpl,et al.  New results on DEPFET pixel detectors for radiation imaging and high energy particle detection , 2003, 2003 IEEE Nuclear Science Symposium. Conference Record (IEEE Cat. No.03CH37515).

[19]  Noise analysis of gallium arsenide pixel X-ray detectors coupled to ultra-low noise electronics , 2003 .

[20]  Giuseppe Bertuccio,et al.  Study of silicon carbide for X-ray detection and spectroscopy , 2003 .

[21]  G. Bertuccio,et al.  Silicon carbide for high resolution X-ray detectors operating up to 100°C☆ , 2004 .

[22]  M. G. Bisogni,et al.  A prototype for a mammographic head and related developments , 2004 .

[23]  C. Lanzieri,et al.  Minimum ionizing and alpha particles detectors based on epitaxial semiconductor silicon carbide , 2004, IEEE Transactions on Nuclear Science.

[24]  S. Cihangir,et al.  Study of temperature dependence of bump bonding for the BTeV pixel detector , 2004, IEEE Transactions on Nuclear Science.

[25]  I. Peric,et al.  FE-I2: a front-end readout chip designed in a commercial 0.25-/spl mu/m process for the ATLAS pixel detector at LHC , 2004, IEEE Transactions on Nuclear Science.

[26]  N. Wermes,et al.  Trends in pixel detectors: tracking and imaging , 2004, IEEE Transactions on Nuclear Science.

[27]  David Blaauw,et al.  Gate oxide leakage current analysis and reduction for VLSI circuits , 2004, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[28]  C.M.H. Chen,et al.  Characterization of a large-format, fine-pitch CdZnTe pixel detector for the HEFT balloon-Borne experiment , 2004, IEEE Transactions on Nuclear Science.

[29]  G. De Geronimo,et al.  Silicon carbide pin diodes as radiation detectors , 2005, IEEE Nuclear Science Symposium Conference Record, 2005.