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A DePMOS structure provides detection and amplification jointly, and it is free of interconnection stray capacitance. To fully exploit the intrinsic low noise of the device an electrical model has been developed. The most relevant parameters have been measured in order to choose an adequate readout electronics. DePMOS can operate in continuous mode, i.e., without applying any clear pulse during the signal processing, and can be read out by a time-continuous shaper amplifier. An unequalled noise of 2.2 electrons rms at room temperature has been measured. In this mode DePMOS can be used, for example, as the readout device for silicon drift detectors. Anyway, DePMOS was developed to be the basic element of an active pixel sensor suitable to cope with the requirements of the XEUS Wide Field Imager. In a matrix arrangement, each pixel must be read out by a time-variant filter. A multichannel integrated shaping amplifier, based on multi-correlated double sampling, has been designed. Spectroscopic resolution obtained filtering the pixel matrix with this readout chip is in agreement with measurements in continuous mode and matches the predictions of the model presented. It has also been experimentally proved that the clear procedure does not introduce additional noise contribution, even in the very low noise range achieved. This qualifies DePMOS as a 'reset-noise-free' device. Index Terms--Active pixel sensor (APS), DePMOS, noise filtering, readout electronics, X-ray detector, X-ray Evolving Universe Spectroscopy (XEUS), X-ray spectroscopy.

For operation at a linear collider the excellent noise performance of depleted field effect transistor (DEPFET) pixels allows building very thin detectors with high spatial resolution and low power consumption. However, high readout speeds of 50 MHz line rate and 20 kHz for the full detector must be reached. A prototype system is presented, using a new DEPFET pixel matrix (128 x 64 pixels), fast steering chips (Switcher II) for row wise operation and a fast current based readout chip (CURO II). The sensors with small linear DEPFET pixels (22 x 36 [micro][m.sup.2]) are optimized for fast readout and high spatial resolution. Measurements show that the complete removal of the accumulated signal charge from the internal gate (complete clear), which is fundamental ['or the foreseen readout mode, is feasible. The current based readout chip CURO II, containing current memory cells, pedestal subtraction and on chip zero suppression for a triggerless operation has been fabricated and tested. First results of a full prototype system are presented. Index Terms--Active pixel sensor, CURO, DEPFET, International Linear Collider (ILC), vertex detector.

Active pixel sensors (APS) based on the depleted P-channel MOSFET (DEPMOSFET) recently produced at the MPI semiconductor laboratory are a promising new type of sensor to cope with the advanced requirements of the XEUS wide field imager, a large area imaging and spectroscopy detector for X-ray astronomy. The DEPMOSFET APS combine high energy resolution, low power consumption and random accessibility of pixels providing for highly flexible readout modes with fast readout speed. In the first prototype production, several design variants of 64 x 64 pixel DEPMOSFET matrices with a pixel size of 75 x 75 [micro][m.sup.2] have been realized. A data acquisition (DAQ) system for evaluation of sensor prototypes has been developed, which allows for a performance characterization of the different designs. For operation, DEPMOSFET device, front-end IC and control ICs are integrated onto a readout hybrid. Device readout is done row by row, addressing and resetting one single matrix row at a time and processing the signals with a 64 channel parallel CMOS amplifier/multiplexer IC of the charge amplifier multiplexer type applying 8-fold correlated double sampling. Addressing and resetting of the matrix rows is done by two control ICs of the SWITCHER type fabricated in a high voltage CMOS technology. A number of readout hybrids has been built, the characterization of the different devices in terms of noise, spectral resolution and charge collection efficiency is in progress. The most promising DEPMOSFET matrix design variants, the DAQ system and measured key performance parameters of the devices are presented. Index Terms--Active pixel sensor (APS), data acquisition (DAQ), DEPFET, imaging, spectroscopy, X-ray, X-ray evolving universe spectroscopy (XEUS).

DEPFET pixel detectors are unique devices in terms of energy and spatial resolution because very low noise operation can be obtained (ENC = [2.2e.sup.-] at room temperature) by implementing the amplifying transistor in the pixel cell itself. Full DEPFET pixel matrices have been built and operated for autoradiographical imaging with imaging resolutions of 4.3 [+ or -] 0.8 [micro]m at 22 keV. For applications in low energy X-ray astronomy the high energy resolution of DEPFET detectors is attractive. For partide physics, DEPFET pixels are interesting as low mass detectors with high spatial resolution. For a linear collider detector the readout must be very fast. New readout chips have been designed and produced for the development of a DEPFET module for a pixel detector at the proposed TESLA collider, containing 520 x 4000 pixels, with 50 MHz line rate and 25 kHz frame rate. The circuitry contains current memory cells and current hit scanners for fast pedestal subtraction and sparsified readout. The imaging performance of DEPFET devices as well as present achievements toward a DEPFET vertex detector for a linear collider are presented. Index Terms--DEPFET, medical imaging, pixel detector, silicon detector.

The [e.sup.+][e.sup.-] linear collider physics program sets highly demanding requirements on the accurate determination of charged particle trajectories close to the interaction point. A new generation of depleted field effect transistor active pixel sensors with 25[micro]m pixel size is currently being developed to meet the requirements in the point measurement resolution and multiple track separation. To minimize the influence of the multiple scattering on the impact parameter resolution, the sensors have to be made as thin as possible. This paper presents a technology based on direct wafer bonding and deep anisotropic etching for the production of ultra-thin fully depleted sensors with electrically active back side. PiN diodes with 50 [micro]m thickness have been produced in this way and the results show the feasibility of this approach. The technology is useful for the production of any kind of thin sensors with active back side (strip detectors, pad detectors, etc.). An integrated support frame outside the sensitive area allows for safe handling and mounting of the thin devices. Index Terms--DEPFET APS, thin silicon sensor, vertex detector.

Recent results of the RD48 (ROSE) collaboration suggest the usage of oxygen-enriched silicon for sensors operated in the harsh radiation environment of future high luminosity experiments. To investigate if the anticipated beneficial properties are still present after full processing of the wafers, full-size strip detectors designed for the innermost ring of the ATLAS forward region have been fabricated on oxygen-enriched silicon by CiS, Germany. These sensors, together with sensors processed in exactly the same way on standard substrates of different thickness, have been exposed to 3 x [10.sup.14] 24 GeV/c protons/[cm.sup.2] at the CERN PS. After irradiation, the sensors went through a controlled annealing up to an equivalent annealing time of 32 d at 25[degrees]C. We are presenting the comparison between these sensors based on I-V and C-V measurements and the investigation of the charge-collection efficiency obtained with a [sup.90]Sr source and fast analog readout at Large Hadron Collider speed. Index Terms--Oxygen enrichment, radiation hardness, silicon strip detector.

X-ray sensitive CCDs with outstanding properties have been developed and produced at the MPI Halbleiterlabor. They contribute to the focal plane instrumentation of two space missions: the European XMM and the German ABR, IXAS satellites. These CCDs, presented here, use exclusively ph-junctions on ultra-pure, high-ohmic silicon for all active components, in particular for the transfer electrodes and the on-chip readout circuitry. Full depletion of the detector chip, a homogeneous and thin entrance window and large pixel sizes can be realized by this technological concept. This concept results in low noise performance, spectroscopic energy resolution, high detection efficiency, radiation hardness and fast readout. With these properties the so-called pn-CCDs ideally match the requirements of the satellites, which are given by the specifics of their X-ray imaging optics as well as the intensity, energy range and dynamic behavior of the objects to be observed.

The results of the first irradiation tests of newly designed silicon microstrip detectors performed with 21 MeV protons at the Max-Planck-Institut, in Heidelberg are presented. The detectors were developed and produced by the semiconductor laboratory of the Max-Planck-Institut in Munich. Novel guard ring structures allow operation of the detectors at voltages exceeding 300 V.