Silicon nitride

About: Silicon nitride is a research topic. Over the lifetime, 32678 publications have been published within this topic receiving 413599 citations. The topic is also known as: N₄Si₃.

Method and device for forming silicon nitride film, and method for preprocessing of cleaning thereof

Abstract: PROBLEM TO BE SOLVED: To provide a method and a device for forming a silicon nitride film, and a method for preprocessing of cleaning the forming device, capable of suppressing the occurrence of hydrochloric acid gas in maintenance operation. SOLUTION: A heat treatment device 1 comprises a reaction pipe 2 for forming a silicon nitride film on a semiconductor wafer 10, by supplying hexachlorodisilane and ammonia; and an exhaust pipe 16 connected to the reactive pipe 2. Before disassembling and cleaning the exhaust pipe 16, the reaction pipe 2 is heated to 500 deg.C to 900 deg.C with a heater 12, and the exhaust pipe 16 and a valve 17 are heated at 100 deg.C to 200 deg.C by a heater 20 for the exhaust pipe. After that, ammonia is supplied from a process-gas inlet pipe 13.

Method for fabricating semiconductor device

Abstract: After forming a gate insulating film on a semiconductor substrate, a silicon film is deposited on the gate insulating film, and a high-melting point metal film is deposited on the silicon film. After forming a hard mask made of a silicon oxide film or a silicon nitride film on the high-melting point metal film, the high-melting point metal film is dry etched by using the hard mask as a mask. After removing a residue or a natural oxide film present on the silicon film through dry etching, the silicon film is dry etched by using the hard mask as a mask. The residue or the natural oxide film is removed while suppressing excessive etching of the silicon film.

UV-enhanced dry stripping of silicon nitride films

Abstract: A UV light-enhanced process for rapidly stripping films of silicon nitride in a dry reaction environment, which may be free of plasma or plasma effluents. This process is carried out in a sealed reactor which allows simultaneous exposure of a substrate wafer to a polyatomic fluorine containing gas which can be photodissociated by UV radiation to produce atomic fluorine and to UV radiation. Silicon nitride stripping rates in excess of 500 Å/min are readily obtainable with UV-stimulated fluorine-based processes, while maintaining the bulk wafer temperature below 300° C. Selectivities for silicon nitride-to-silicon oxide etching of greater than 30 can be achieved for the stripping of silicon nitride LOCOS mask layers in the presence of field oxide and pad oxide layers when a chlorine or bromine containing gas which can be photodissociated by UV radiation to produce atomic chlorine or bromine is used in mixture with the fluorine containing gas. Selectivity and etch rate are controlled through UV lamp exposure, substrate temperature, and additions of nitrogen diluent, and photodissociable chlorine or bromine containing gases. The process addresses many of the limitations of plasma-downstream etch tools for dry silicon nitride stripping, including complete elimination of charged particles and sputtered contaminants associated with plasma effluents.

Transient Thermal Response of a Rotating Cylindrical Silicon Nitride Workpiece Subjected to a Translating Laser Heat Source, Part I: Comparison of Surface Temperature Measurements With Theoretical Results

Abstract: Laser-assisted machining (LAM), in which the material is locally heated by an intense laser source prior to material removal, provides an alternative machining process with the potential to yield higher material removal rates, as well as improved control of workpiece properties and geometry, for difficult-to-machine materials such as structural ceramics. To assess the feasibility of the LAM process and to obtain an improved understanding of governing physical phenomena, a laser assisted machining facility was developed and used to experimentally investigate the thermal response of a rotating silicon nitride workpiece heated by a translating CO 2 laser. Using a focused laser pyrometer, surface temperature history measurements were made to determine the effect of rotational and translational speed, as well as the laser beam diameter and power, on thermal conditions. The experimental results are in good agreement with predictions based on a transient three-dimensiona numerical simulation of the heating process. With increasing workpiece rotational speed, temperatures in proximity to the laser spot decrease, while those at circumferential locations further removed from the laser increase. Near-laser temperatures decrease with increasing beam diameter, while energy deposition by the laser and, correspondingly, workpiece surface temperatures increase with decreasing laser translational speed and increasing laser power. In a companion paper (Rozzi et al., 1998), the detailed numerical model is used to further elucidate thermal conditions associated with laser heating and to assess the merit of a simple, analytical model which is better suited for on-line process control.