The deuterium (D) bubbles formed in W exposed to high flux D plasma were researched by scanning electron microscopy and transmission electron microscopy. After D plasma exposure at 500 K and 1000 K, a layer of nano-sized bubbles were homogenously distributed in W subsurface region. The D bubbles were homogenously nucleated due to the high D concentration, and the nucleation process is not related to the vacancy defects. At low temperature (500 K), D bubbles can grow by surface blistering, which caused different nano scale morphologies on different surfaces. At high temperature (1000 K), D bubbles mainly grow by vacancy clustering, which caused pinholes on the surface.

Diamond-like carbon (DLC) films were deposited on both the untreated and the prior carbon ion implanted Ti6Al4V alloys by plasma enhanced chemical vapour deposition (PECVD). The tribological behaviours were evaluated by conducting reciprocating wear tests against ZrO 2 using a ball on disc tribotester. The effect of ion implantation dose and zone on mechanical and tribological behaviour of DLC films was studied by means of nanohardness and nanoscratch tester, SEM and three-dimensional surface profiler. The duplex treatment dramatically increased the surface hardness and bonding strength of film/substrate. Both carbon ion implantation and PECVD improved the wear resistance of titanium alloy, whereas the combined process of carbon ion implantation with the dose of 10 16 ions cm 22 and PECVD offered the best wear resistance by a reduction of 94?3% in wear volume in comparison to untreated alloy. The cracks and deformations that induced local flaking failure under high contact stress played an important role in the wear and failure mechanisms.

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This paper presents the development of a prototype pixel readout ASIC for CZT detectors fabricated in a 180 nm CMOS process. It consists of a 32×32 array of pixels in 100 µm pitch and the EOC (end-of column) circuit for control and data readout. Each pixel integrates a charge sensitive preamplifier, a CR-RC shaper, two discriminators, two 12-bit counters and registers, allowing us to acquire and readout images simultaneously. A local 6-bit register has also been integrated for each pixel for calibration enable and threshold fine tuning, which can be programmed through a SPI slow control interface.A dedicated chip evaluation system was developed and the initial test results showed that the chip worked well. The power consumption was measured to be 38.9 µW per pixel, which could be adjusted by the master bias unit. The gain of the analog front-end was approximately 77.3 mV/fC and the ENC was less than 100 electrons for different shaping times and the input capacitance of about 100 fF. The results were in good agreement with our design specifications. More detailed design and test results will be discussed in this paper. K: Electronic detector readout concepts (solid-state); Front-end electronics for detector readout 1Corresponding author.