Sin is silicon nitride, and semiconductor Sin is the third-generation semiconductor to be emitted based on silicon nitride.
Structural ceramics include wear resistance, height, heat resistance, heat shock resistance, hard, high rigidity, low expansion and heat insulation ceramic materials; Functional ceramics include ceramic materials with acoustic, optical, electrical, magnetic, biological, chemical, nuclear and other functions. The basic physical properties of Si3N4 under atmospheric pressure, Si3N4 has no melting point, and the thermal expansion coefficient of silicon nitdrive directly decomposed at about 1870℃ is low. In addition to Si02(quartz) in ceramic materials, the thermal expansion coefficient of Si3N4 is almost low, which is 2.35 ×106 \/ K, about 1\/3 of A1203. It is 18.4W\/(m·K), and has a high degree, so its thermal shock resistance is very good, second only to quartz and glass-ceramics, thermal fatigue performance is also very good room temperature resistivity of 1.1x10 \"Q·cm, 5.7 ×106Q·cm at 900C, dielectric constant of 8.3, dielectric loss of -- 0.1
1. Basic properties of silicon nitride semiconductor
Ceramic beads of silicon nitride can reach HRC80 degrees, and the limit high temperature is about 800 degrees
It is a high temperature insoluble compound with no melting point and strong resistance to high temperature creep. The load softening point of reactive sintering silicon nitride without binder is above 1800℃
1285 degrees and calcium nitride reaction to calcium nitride silicate, 600 degrees to reduce the transition metal, the release of nitrogen oxides, bending strength of 147MPa
The diagram shows the three-point bending test diagram of a three-layer composite beam composed of coating and matrix. The relationship between deflection and load is theoretically tensiletest type stress in the diagram of tensile specimen Fig. Moreover, the position of the neutral axis of the three-layer composite beam is to determine the relative value of the stress intensity factor representing coating and matrix respectively. Based on the linear section (elastic section) of the load-application point displacement curve obtained by experiments, the elastic modulus of the coating can be obtained by equations (2) and (3)
Silicon nitride is a covalent compound, so the atoms are combined with a strong covalent bond, so it has a high hardness and melting point
2, silicon nitride semiconductor material performance
Silicon nitride ceramic material has high thermal stability, strong reaction ability and high product size excellent performance, because silicon nitride is a covalent compound with high bond strength, and can form an oxide protective film in the air, so it also has good chemical stability, below 1200℃ is not oxidized, 1200~1600℃ generated protective film can prevent further oxidation, And is not infiltrated or corroded by aluminum, lead, tin, silver, brass, nickel and many other molten metals or alloys, but can be corroded by magnesium, nickel-chromium alloy, stainless steel and other molten fluids, in recent years, with the promotion of laser technology, laser surface treatment technology is also used as a new surface coating treatment technology for Si3N4 ceramic bearing friction contact surface coating treatment. Influence of the number of grain boundary phases: Select different number of grain boundary phases of ceramics, corrosion comparison found that: in the initial reaction, the corrosion rate is basically the same; With the further progress of corrosion, the corrosion rate diverges, the passivation layer appears, and the more the number of grain boundary phases, the more serious the corrosion of silicon nitride
The semiconductor SIN is silicon nitride and it has two crystals, namely the low temperature type α-silicon nitride and the high temperature type β-silicon nitride, and one amorphous. When the powdered Si3N4 is heated at 1200℃ for more than 4h, it forms the α- type, and when heated at 1450℃ for 2h, it forms the β- type. The α-type is hexagonal crystal system. The beta - type is cubic crystalline. The pure is colorless, but it is usually seen as containing trace impurities, which are gray, grayish brown or black. Molecular weight 140.29. The relative density is 3.44. This product is insoluble in water, acid and alkali.