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NiOx thin films were grown on quartz-glass substrates by two-step process: oxidation of metal Ni thin film which was obtained by vacuum evaporation method. The structural, optical and electrical properties of NiOx thin film were investigated by X-ray diffraction, absorption spectra and Hall measurement, respectively. The oxidation temperature could influence the structural, electrical and optical properties of NiOx thin film. At lower oxidation temperature (623 K), the oxidation process was not finished completely. With the increase of oxidation temperature, Ni thin films were totally oxidized into p-type NiO thin films and the optical absorption edge became steeper. Furthermore, the conductivity and carrier concentration of p-type NiO thin film decreased with the increase of oxidation temperature.

The ion barrier film of microchannel plate (MCP) plays a most important role in the third generation low-light level image intensifier to prevent the feedback of positive ions, protect the photocathode and prolong the operating life of image intensifier. In this paper, the influence of high-temperature degassing on the performances of the ion barrier film and the MCP itself were investigated by the experiments. The high-temperature degassing and the corresponding measurement system of MCP were shown, the detailed technology process was given, and the changes of the ion barrier film's morphology and the MCP's electrical performance after high-temperature degassing were compared. For a MCP with an ion barrier film, it was found that the electron gain decreased, the bulk resistance increased, the grain size of the ion barrier film increased and the dead-voltage decreased after high-temperature degassing.

ZnO is the most SURPLVLQJPDWHULDOIRUWKHDSSOLFDWLRQRIDQXOWUDYLROHW 89 GHWHFWRU . However the shortage of p-type ZnO becomes the biggest blockage for fabricating ZnO-based semiconductor device. In this paper, following experiments had been done: Firstly, the zinc nitride powders were synthesized through the nitridation reaction of Zn power with NH 3, and the optimized synthesis temperature was at 600 . Next, the zinc nitride powder was fabricated into a zinc nitride sputtering target by a single pressing process. Th irdly a thin layer of zinc nitride film was formed on silicon and quartz substrate using magnetron sputtering method. Fourthly, the zinc nitride film was oxidized into p-type ZnO, and the best optimized temperature for forming p-type ZnO by oxidizing Zn 3 N 2 thin film was at 500 . Lastly, the ohmic contact for p-ZnO and ZnO based detector were fabricated. It was found Al and Ni/Au showed ohmic contact properties to n- Si and p-ZnO, respectively, and the p-Zn O/n-Si junction as a UV detector was feasible. Keywords: Znic nitride, p-type ZnO, ohmic contace, UV Detector

The MEMS silicon-micro-machining is the main MEMS technology, which includes the surface-silicon-micro-machining and the bulk-silicon-micro-machining technology; however the bulk-silicon micro-machining technology has a wide application. In this paper, the formation procession of electron multiplier on n-type Silicon substrate by bulk-silicon-micro-machining technology was investigated. A series of electrochemical etching experiments and tests were carried out in three poles electrobath system using HF electrolyte with different concentration. The rate of photoelectrochemical etching on the macropore depends on a few technological parameters, such as doping concentration, operating bias, illumination intensity of the light, HF concentration, and so on. It was found that the formation possibility of the macropore array is directly correlated with crystal orientation of n-type Silicon substrate.

Microsphere plate (MSP) is a new type of electron multiplier device. It is similar to the traditional microchannel plate (MCP) in dimensions and model of operation. Compared with the MCP electron multiplier, the MSP has some unique characteristics such as a high electron gain, without ion feedback and easy to be fabricated, thus it is widely used in the fields of imaging and detecting. However, there are some key technologies to fabricate a satisfied MSP. In this paper, the whole fabrication process of MSP was introduced and some of major processes such as the formation of glass beads, the sintering of MSP body, and the formation of dynode and electrodes were specially discussed. At the end of the paper, the optimal processed for the fabrication of MSP was given.

The photomultiplier tube (PMT) that can work in different wavelength is an important detector device in remote sense technology. Microsphere plate using glass beads 50to 70μm in diameter sintered together is the core component of the microsphere plate photomultiplier tube It is a novel two-dimension electron multiplier. The electrons gain for a single plate is about 1017 and do not have the phenomenon of ion-feedback. Furthermore the fabrication process is very easy. In this paper, much interest was put on the microsphere plate photomultiplier tube. Based on the analyses from the theory and the experiment result, we point out the key technology for fabricating PMT is how to obtain glass beads with narrow range in diameter and how to sinter the glass beads with a sufficient pylome. Factors affect the gradating technology and sintering process along with the solution to them is presented. In the last, the structure scheme and technological characteristic for fabricating microsphere plate photomultiplier tube were given. The pulse rising-time of MSP-PMT is below 400ps suitable to the detection of high-speed pulse. As easy to be fabricated and has great advantage over MCP multiplier in the ratio of performance to price, the microsphere plate photomultiplier tube is a promising dim-light detector.

In this paper, numerical analysis was investigated for the double-clad fiber lasers and experimental study on the Yb3+-doped double-clad fiber lasers was performed. The results shown that the output power increased monotonically with absorbed power, and in lossy cavity the output power is less than in the lossless cavity. The output power decreases for the lossy fiber with the reflectivity of output coupler. There was an optimum fiber length to reach a maximum output and the optimum length was mainly dependent on the loss coefficient. In experiment we obtained an output power of 21.6W, slope efficiency of 54% by using Yb3+-doped double-clad fiber and 40W LD pump source.

The MCP ion barrier film in low-light-level imaging tube and its process techniques were introduced in this paper. The electron transmittance of this film was studied. The results of half field-of-view testing comparisons and the concept of dead voltage were presented. The dead voltage curve and the relation between dead voltage and thickness of film were tested. The composition of film was analyzed by XPS.

The formation of deep macropore array of p-type Silicon in HF electrolyte has been investigated. Then a series of electrochemical etching experiments and tests were carried out in three poles electrobath using different concentration HF electrolyte. HF concentration is a very important factor that determined whether electrochemical reaction was accomplished or not. By means of theoretical analysis and investigation, it is generally assumed that etching proceeds through sequential reaction of Si-H groups with F- to form Si-X, which determined whether electrochemical etching reaction was carried out or not. The electrochemical etching of p-type Silicon macropore array in aqueous fluoride solutions is satisfied with economic requirements for costs of fabricating deep macropores. The consequences are benefit to Silicon electrochemical deep macropore array etching technology.

A New type of X-ray imaging intensifier was studied and developed. This intensifier combined with a little focal spot X-ray tube and a miniature high voltage power supply. Our product had performances of small volume, light weight, portable, high luminosity, Low X-ray radiation density and real-time imaging in daylight. The Lixiscope had also characteristics of simple structure, simple process, long lifetime, low cost and easy to application and promotion. The qualification of the imaging tube and the system: field range 50 mm, brightness 15 - 20 Cd/m2, screen resolution greater than or equal to 5 lp/mm, X-ray tube current 0.05-0.10 mA, target voltage 40 - 60 KV (continuous adjustable), DC/AC available, portable 2.5 Kg. To improve the X-ray imaging intensifier, we adopted several technologies as below. The little focal spot X-ray tube (0.5 mm2) and X-ray collimator was used to increase the resolution, maximum 10 lp/mm, the fiber faceplate or light cone output window to increase brightness and field range, nd the large area and high resolution MCP to increase field range. So, the developed X-ray imaging intensifier had found the widely application.

Microchannel plate (MCP) is a device of two-dimension array electron multiplier. The detection ability to 40 - 60 KeV X-ray for MCP was increased by coating the halide such as CsI, CsBr and KBr on input plate of MCP, that forming a reflection X-ray sensitive film in the channel with depth of 2 - 3 times of diameter below the input plate. Experiment results show that the output response of MCP with variable density structure CsI to X-ray is about 5 - 6 times higher than that with constant density structure, and of one order of magnitude stronger than that without coating the film. Comparatively, the output response of MCP with CsI sensing film is best, CsBr medium and KBr bad. The response characteristics of MCP with CsI to X-ray related to film materials, structure, component distribution and process. Several experiment curves denoted the response characteristics to X-ray at different target voltage and current. The results basically accorded with the theory about quantum detection efficiency of reflection X-ray cathode. This new MCP reflection X-ray sensitive film of variable density halide has been successfully applied in X-ray imaging detecting devices. The corresponding detection system will find widely and potential applications in the field of medical diagnosis, nondestructive evaluation and security inspection, etc.

This paper reports on a silicon mcrochannel arrays prepared based on bulk-micromachining technology, dry etching technology and electrochemical process respectively. In dry etching, a silicon microchannel plate (Si-MCP), with 15-30 aspect ratio of the microchannel, 6-20 µm, 6-8 µm space and 150-300µm depth, were prepared by Inductively Coupled Plasma (ICP). The phenomenon ofplasma etching lag and the morphology ofthe microchannel array in dry processing were analyzed and discussed.In wet process, both p-type and n-type silicon was selected as the substrate for microchannel arrays. A inducing pit arrays was first prepared by oxidation, lithography, KOH etching, and then a square channel arrays that has 4 µm length of side and 2 µm space were formed by electrochemical etching in hydrofluoric acid in three poles electrolyzing cell, which can yield straight holes with high aspect ratio. The electrochemical mechanism of silicon anisotropy etching, the parameters of three pole electrolyzing cell, and the inducing pit and channel morphology were investigated and discussed. The results shows that the high aspect ratio of silicon microchannel arrays can be made by both dry and wet etching processes. The ICP process yield a microchannel arrays with uneven, re-entrant, notched and ripples surface within the channel. The electrochemical process for silicon microchannel arrays has lower cost than ICP process.

A silicon microchannel plate (Si-MCP), with 15-25 aspect ratio of the microchannel, 6-20 microns diameter and 6-8 microns space, was prepared by Inductively Coupled Plasma (ICP) and LPCVD. The inner surface topography of microchannel was surveyed, the bulk resistance 7.3 mega ohm and electron gain 110 of MCP were tested by ultraviolet optoelectronic method. The plasma-etching lag in processing the microchannel array was analyzed and discussed. Finally, we compared the electron gain of silicon microchannel plate with traditional glass one. Our work proved the feasibility of making Si-MCP by microfabrication and semiconductor process.

The photoemission characteristics of aluminum (Al) and gold (Au) thin film photoelectric cathodes were studied. The metallic cathode stability after exposed to air was investigated. The results of the experiments and study on its photoemission were given, and the application prospect of surface emitter in near UV region was proposed.

In this paper, the characteristics and applications of the window materials within the range of UV, cathode in near UV, and the analogue imaging system of the double-proximity type in near UV with the Au thin film cathodes were introduced.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper introduces a new structure X-ray cathode consisting of new structure haloid coating integrated on the input surface of MCP that is applied in single proximity x-ray intensifier. The current response characteristics of different structure CsI, CsBr and KBr cathodes are compared. The conclusion of excellent output response of the dense-loose-dense three-layer new structure CsI Cathode in the energy range 40 - 50 Kev is obtained.

A radiation-induced leakage current model in deep submicron bulk silicon N-channel metal-oxide-semiconductor field effect transistor (NMOSFET) is proposed in this paper for circuit simulations. The model takes into account the impact of the substrate doping concentration, the angle of shallow trench isolation (STI) region, and the junction depth of source/drain, which can predict the off-state leakage current of the NMOSFET with STI region irradiated at different radiation doses. The model is verified by comparing with the experimental results. The model can be easily implemented into the circuit simulator to evaluate the impact of total ionizing dose effect on the performance of circuit.