THERMID, made of acetylene-terminated polyimide oligomers, was developed by National Starch & Chemical Co. It is capable of forming thicker deposits than conventional polyimides. It is a candidate for a broad array of electronic and optoelectronic applications, including passivation coating, alpha-particle barrier, interlayer dielectric, encapsulation of discrete devices and IC, optical waveguide, and multilayer dielectric for thin hybrids. The study and evaluation of electrical and optical properties of THERMID polyimide give more support to their application in the semiconductor industry. DC Electrical Properties of THERMID Polyimide EL-5010 Bulk ResistivityIn order to measure the very high resistivity of THERMID, a Keithley 236 Source-Measure Unit, with current detection limit of 10 fA (DC) was used as the voltage source and current measurement equipment. A variable temperature test fixture which can effectively reduce the noise level was designed. The measurement was under the control of an IBM 386 AT personal computer (Fig.1). p-Si wafers(10-12 ohmcm) were cleaned by using RCA technique[1]. All microelectronic processing operations were performed in a class 100 clean room facility. Each Si wafer was spin coated with the THERMID thin film. The curing procedure was as follows: 180 OC ( 30 min.), 300 OC (60 min.), and 400 OC(15 min.). The back of the wafer was then sanded to get off the SiO 2 and deposited with a layer of aluminum thin film as ohmic contact. On the side coated by THERMID film, aluminium(or indium) spots were deposited. These spots served as positive electrodes in the test. The sample, which was treated as a capacitor with the THERMID as its dielectric, was then put in the test fixture and double shielded. The bulk resistivity of the THERMID was obtained by measuring the leakage current as a function of the applied voltage, the area of the contact, and the thickness of the THERMID film. The measurements revealed that the room temperature bulk resistivity of THERMID EL-5010 films of thickness of 0.96 -2.56 jum is no less than 1x10 16 ohm-cm. Temperature dependence of THERMID EL-5010 bulk resistivity was also measured (Fig.2).Breakdown Voltage When the applied step voltage was increased to such a point that the corresponding leakage current suddenly increased much faster than before, the breakdown occurred. After that point, decreasing step voltage could not make the current decreasing along the same path it increased before. The breakdown voltage of the 1 um THERMID EL-5010 thin film was measured as 350 volts.

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In the recent years, contour-based shape representation is an important issue in the object recognition research area. In this paper, a new shape descriptor A-DCE is proposed based on DCE and DP for contour deformation and recognition. Firstly, the object contour is evolved adaptively by DCE to extract the contour information with important visual parts. Secondly, the costing feature descriptor is computed by Shape Contexts. At last, shape similarity is measured by DP algorithm based on SC costing descriptor. The experimental results conducted on MPEG-7, Kimia and Swedish Leaf shape data sets evaluate the robustness of the proposed on deformed target, and the operational efficiency and retrieval accuracy are both improved.

Ceramics, as a commonly used insulating and thermally conductive material, has a wide range of applications in the field of micro-nano manufacturing. In recent years, research on ceramic bonding has also increased. However, ceramic bonding has some problems such as bonding failure and low bonding quality. Learning from other commonly used bonding materials, the important factor for the success of bonding is the surface properties of the material. Therefore, in this study, the surface of ceramic was treated by dielectric barrier discharge (DBD) to improve surface properties. The effects of dielectric barrier discharge on the surface properties of ceramic is investigated from the three aspects: hydrophilic angle, surface energy and surface morphology. In the dielectric barrier discharge experiment, blind via glass is used as the blocking medium for the upper electrode. The lower electrode is covered by ceramic, and the ceramic is also the material to be treated. The influence of processing time, discharge voltage and discharge frequency on the treatment effect is investigated in the experiment. The hydrophilic angle and surface energy of the treated ceramics are measured and calculated by contact angle measuring instrument, and the surface morphology was observed by scanning electron microscopy. The results show that the longer the discharge treatment time is, the larger the discharge output voltage is, the smaller the discharge gap is, the faster the hydrophilicity of the surface of the ceramic sheet is, and the higher the activation energy is. The damage of the ceramic surface after treatment is small, and the impurities on the surface are destroyed. In general, the surface properties of ceramics after dielectric barrier discharge treatment are better than before.