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  Although the processing of   silicon carbide substrate  is difficult, in order to make the application of single crystal silicon carbide in electronic components become the future direction of development, so that silicon carbide devices are large-scale application and promotion, it is necessary to find a way to solve the problem of difficult silicon carbide processing.   At present, the SiC material processing technology mainly has the following processes: directional cutting, chip rough grinding, fine grinding, mechanical polishing and chemical mechanical polishing (fine polishing). Among them, chemical-mechanical polishing is the final process, and its process method selection, process route arrangement and process parameter optimization directly affect the polishing efficiency and processing cost.   However, due to the high hardness and chemical stability of SiC materials, the material removal rate in the traditional CMP polishing process is low. Therefore...

  Silicon carbide (SiC) as a high performance semiconductor material, because of its excellent physical and chemical properties, in power electronics, radio frequency microwave, optoelectronics and other fields show great application potential. However, the high hardness and stable lattice structure of silicon carbide pose great challenges to its polishing process. This article will focus on the reasons for the difficulty of polishing   silicon carbide substrate , in order to provide reference for the research and application in related fields.   First, high hardness and brittleness caused by polishing problems The ultra-high hardness of silicon carbide is one of its remarkable characteristics, and the Mohs hardness is up to 9.5, second only to diamond. This high hardness characteristic makes it necessary to use equally high hardness abrasives and tools in the polishing process. However, high hardness abrasives often lead to rapid wear of polishing tools during the polish...

  Zirconia ceramics is a new type of high-tech ceramics, which in addition to high strength, hardness, high temperature resistance, acid and alkali corrosion resistance and high chemical stability conditions of precision ceramics, but also has higher toughness than ordinary ceramics   ZrO2 ceramic  can be used in various industries, such as  shaft sleeve ,  bearings , cutting components, molds, automotive parts, and even the human body. In the field of consumer electronics, zirconia ceramics because of its hardness close to sapphire, but the total cost is less than 1/4 of sapphire, its bending rate is higher than glass and sapphire, non-conductive, will not shield the signal, so it is favored by fingerprint recognition module patch and mobile phone back cover.   Zirconia ceramic ring  is a kind of inorganic non-metallic mechanical part made by sintering at high temperature, which has the advantages of high temperature resistance, corrosion re...

  Brazing is the most important process in the process of   AMB silicon nitride substrate , and the preparation of active brazing filler metal and active metal brazing are the key and difficult points at present.   Ti, Zr, Hf, V, Nb, etc. are common active metal elements that can infiltrate  silicon nitride substrate  surfaces and are widely used for active sealing between ceramics and metals. Among them, the Ag-Cu-Ti alloy with Ti as the active element is the most studied and most widely used active filler metal. It can wet most ceramic surfaces at the temperature of 800~950 ℃, and the brazing head has high strength and stable performance, so that the sealing between ceramics and metals, ceramics and ceramics can be better realized.   The use of Ag-Cu-Ti active filler metal includes the following four forms, which vary with the form of Ti element and the combination of filler metal: a. Pre-coated Ti powder (or TiH, powder) paste, and then add pre...

  With the rapid development of power electronics technology, silicon carbide (SiC) power devices with their excellent high temperature stability, high energy density and low loss characteristics have shown great application potential in new energy vehicles, smart grids and efficient energy conversion fields. However, to fully exploit the performance advantages of SiC devices, it is crucial to select the right packaging substrate. Among the many ceramic substrate types, the   active metal brazed (AMB) silicon nitride (Si3N4) substrate  has gradually become the preferred solution for the packaging of SiC power devices with its unique advantages. The purpose of this paper is to explore why AMB ceramic substrates, especially Si3N4-AMB substrates, stand out and meet the packaging needs of SiC power devices for high temperature, high power, high heat dissipation and high reliability.   As the core component of power device package, the performance of ceramic substrate dir...

  Because of its high hardness, high strength, excellent wear resistance and chemical stability, silicon nitride ceramics show a wide range of application prospects in ceramic bearings, cutting tools and high temperature structural materials. In this study, self-made α-Si3N4 powder was used as raw material, combined with nano-scale Y2O3 and Al2O3 as sintering additives, and   silicon nitride balls   were prepared by pressure sintering process with relatively low cost. The effect of sintering temperature on the densification, phase composition, microstructure and mechanical properties of ceramic balls was discussed in this paper, aiming to optimize the preparation process and improve the comprehensive properties of ceramic balls.   1.1 Raw materials The raw materials used are silicon nitride powder (self-made,α-Si3N4 mass content >93%, oxygen content <2%, median particle size D50<1μm), nano-yttrium oxide (sinopyma reagent, purity >99.9%, median particle si...