| 摘要 |
A method for high rate silicon nitride deposition at low pressures, including a method of operating a CVD reactor (56) providing a novel combination of wafer temperature, gas flow and chamber pressure resulting in both rapid deposition and a uniform, smooth film surface. According to the method, a wafer (60) is placed in a vacuum chamber wherein a reactant gas flow of silane and ammonia is directed in parallel with the wafer surface via a plurality of temperature controlled gas injectors, the gas being confined to a narrow region above the wafer. The gas is injected at a high velocity, causing the deposition rate to be eliminated only by the rate of delivery of unreacted gas to the wafer surface and the rate of removal of reaction byproducts. The high velocity gas stream passing across the wafer has the effect of thinning the layer adjacent the wafer surface containing reaction by-products, known as the "boundary layer", resulting in faster delivery of the desired reactant gas to the wafer surface. The rapid gas flow also reduces the gas residence time above the substrate surface, and sweeps out unwanted reaction by-products resulting in a further increase in the relative concentration of the desired reactant species and reduced incorporation of unwanted reaction by-products in the deposited film.
|
