| Today, miniaturized and high frequency products become tow important trend of development in electronic industrial. It can't meet with the need of medium speed and high-speed development more and more because tradition thick-film technology exist many shortcomings. Therefore, under the current drastically competitive environment, it is urgent to need a new technology with small-size, high-precision, high-stability and high-reliability HC can be rapidly fabricated without mask. Size of film component is decreased bigger and bigger because they are piled many coatings in space and integrated by bare components. At the same time, it has many merits when components are directly integrated in circuit, for example, length of interconnection lines is short, numbers of spot weld decrease, dead resistance and circuit noise debate, and cost of product is down. For the development of high-density film components are assembled in the inner and outer circuits, which will cause the less area of substrate and space used, thereby get to the aim of miniaturized and high-density integration.With the support of National Natural Science Foundation of China and National"863"Hi-Tech Research & Development Program of China, a new manufacturing technology who is passive components and circuits rapidly fabricated by laser micro- cladding on ceramic substrate was firstly presented in this paper around the world, passive components included resistor, capacitor and inductor etc. Some key issues were amply studied, for example, forming principle of pre-set film and the fabrication of components or integrated modules, on the basis of above-mentioned information, Precision Spray system was exploited for the forming of pre-set film, and current equipment was improved. The main research results were shown as following:External circuit, thick-film electronic components and integrated modules were directly rapidly fabricated on ceramic substrate by laser micro cladding. Its processing method was that electronic paste was sprayed in set unit by Precision Spray system and pre-set film was dried by the heating of current flow, and then laser scanned dried film according to pre-set parents, and then substrate was cleaned and scanned area were welded on the substrate. The minimal pattern resolution gained by this technology is 20μm/40μm, which largely breaks through the boundary value gained by tradition thick-film technology. Properties and bond strength of circuits and components fabricated by this technology were excel to tradition thick-film technology by the analysis of micro morphology, composition, electronic property, mechanical property and interface behavior between conductive lines and components, particularly interface reaction hasn't between different materials, which resulted in a good reliability, stability and repeatability of product, and met with the developing requirement of electronic industry and market.Precision Spray system was exploited and made use of the forming of surface uniform pre-set film on ceramic substrate. At the same time, for different components were fabricated by different materials, therefore, the effect of pre-set film thickness and paste characteristic on quality and properties of electronic film had a systemic research, and the limit values of different pastes were gained, which was in favor of laser scanned subsequently.The effect of pre-set film thickness and laser processing parameters on thickness, width, quality and property of conductive lines and components was studied, and thickness and width ranges of electronic films were established by the limit ranges of scan velocity and laser power as well as defocused length and center distance between lines. The root cause resulting in the limit value and the effect on quality and property of ultimate products were simply analyzed, and the optimal laser processing parameters scanning the wider area were gained, results were shown as following: conductive line was fabricated by the following parameters, for example, 4μm thickness of pre-set film, 1.0x104W/mm2 power density, 5mm/s scan velocity, focused length; Resistor film was fabricated by the following parameters, for instance, 15μm thickness of pre-set film, 35Watt laser power, 3mm/s scan velocity,0.05mm center distance between lines, focused length; Dielectric film of capacitor was fabricated by the following parameters, for example, 6μm thickness of pre-set film, 25Watt laser power, 2mm/s scan velocity, 0.2mm center distance between lines, 1.5mmdefocused length; Magnetic dielectric film of inductor was fabricated by the following parameters, for instance, 4μm thickness of pre-set film, 6.4mmdefocused length, 35Watt laser power, 3mm/s scan velocity, 0.01mm center distance between lines.Recur to some analysis technology such as thermal analysis, SEM, EDS and probe etc, this paper detailedly analyzed the relationship of microstructure, element distribute, phase and interface behavior of components and conductive lines fabricated by this technology and traditional sintering technology along with the combination of them, and discussed their forming mechanism of film, adherence mechanism and conductive mechanism by the analysis of experimental results and theory, results were shown as following: compared with traditional sintering technology , components and conductive lines rapidly fabricated by the technology of laser micro-cladding were high quality and good property as well as high reliability, and diffusion of composition isn't in the interface of different materials, however, property and quality of components scanned by laser became bad if they were sintered by high temperature again.Summing up above mentioned, the novel technology of laser micro-cladding and rapid fabrication is a technology of direct writing with merits, for example, no mask, high speed, high precision. Comparison with traditional technologies, the technology is fit to new product research and development as well as small-scale and versatile production because it has many merits, for instance, low cost, high efficiency, high quality and high reliability etc. Moreover, the technique can be applied to micro-soldering and the fabrication of hybrid components having complicated specific function etc, it has the maximum ductility and wide applications.
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