Hybrid pixel detectors

The detection efficiency of silicon is low above 20 keV. A higher-Z, pixellated, detector is therefore included behind the silicon CCD. The silicon is therefore thinned down to the active thickness to minimise unwanted absorption. Due to the depth of focus of the optics, the second detector may be up to 15 mm beJiind the silicon CCD. In order to determine changes in source continua above 20 keV and to resolve cyclotron lines, we require to combine high detection efficiency with an energy resolution of between 1-2 keV over the energy band 20-60 keV. We envisage the use of a hybrid array of diodes constructed on... 

In preliminary tests performed on the X-ray camera a subarray of 5x5 strips was used to obtain a 25 pixel detector each strip coupled to a hybrid charge sensitive preamplifier (CSP), model CS 507, produced by Clear Pulse (Tokyo) in a modified version with external input FET and a resistive feedback loop CSP is characterised by an equivalent noise (r.m.s.) of about 1 keV. Pulses from CSP... 

In this section, we describe two pixel options which are being considered hybrid pixel arrays in which the readout electronics and the silicon detector array are constructed as two separate silicon chips that are then bump-bonded together, and the monolithic pixel detector in which the readout electronics is on the same substrate as the silicon detector. R D for both technologies is currently being pursued for potential use at the SSC laboratory. 

PrelimiTKn y Dasifjn of a PEP-II Vertex Detector Based on Hybrid Pixel Airays... 

S. Shapiro et al, Proposed Use of Hybrid Pixel Arrays Using the Data Push Architecture for a Vertex Detector at a SLAC Asymmetric D Factory, BaBar Not(3 105, May 1993. 

For infrared microspectroscopy, single-element detectors are used for point and mapping measurements. More recently, array detectors have been applied for spectroscopic imaging in the infrared. In infrared focal plane arrays, the monolithic silicon design used in CCDs is replaced by a hybrid construction. In a hybrid detector, photon detection occurs in a semiconductor layer (indium antimonide, mercury cadmium telluride, and doped-silicon are typical detector materials), while the readout and amplification stages are carried out in a silicon layer. The two layers are electrically connected at each pixel through indium bump-bonds . Other innovations such as microbolometer arrays also show promise for spectroscopic imaging applications. 

At the time of the ESA Call for Proposal, there was no detector avmlable in Europe for the long wavelength channel. A specific development was undertaken at the Laboratoire frifrarouge du CEA-LETI in Grenoble. It is a photoconductor array in Si Ga hybridized by Indiiun bumps to a direct voltage readout circuit. It has 32 X 32 pixels, a 100 /joa pitch with a thickness of... 

Two 256X256-pixel arsenic-doped-silicon (Si As) impurity band conduction (IBC) hybrid detector arrays developed by Hughes Technology Center have been evaluated for space-based astronomy applications. Potential applications include instrumentation on orbiting astronomy platforms such as the Space Infrared Telescope Facility (SIRTF). 

Dhe detector array is a bulk 10X64 pixel Si As hybrid device manufac- d by Hu es Aircraft Co. The detector is assembled from a wafer of tnide-doped silicon material bump-bonded with a matrix of indium con- s to a Hughes CRC-310 direct readout (DRO) integrated circuit mul-exer dup.The array operates as 10 linear rows of detectors in parallel, ii 10 readout chains. The pixel size is 100X100 /aa with a separation of /xm center to center,and the operating temperature of the array is 10-12 The optical system of the camera consisting of two convex ZnSe lenses, ndes a pixel field of view onto the array of 1.23 /pix. 

After detector-fanout testing has identified detector wafers that exhibit high performance, the detectors from these qualified wafers are hybridized to readouts using HTC s indium bump bonding technology. These hybrids are then thorou y characterized in HTC s sophisticated hybrid test lab. Noise level and uniformity, response level and uniformity, and number of degraded pixels are measured. Fully automated test stations perform all measurements and an dysis and report the data in numerical, histogram, and pixel map displays. 

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