主权项 |
1. An apparatus for depositing a layer on a semiconductor wafer by means of vapor deposition, comprising
a susceptor having a front side facing a semiconductor wafer to be coated, and a rear side; a shaft for rotating the susceptor, the shaft having an upper end and a lower end, and a channel extending from the lower to the upper end; a gas distributor head fixed to an upper end of the shaft, a line for feeding a cooling gas from a cooling gas source to the lower end of the shaft, from where the cooling gas passes through the channel to the upper end of the shaft and into the distributor head and is directed to the rear side of the susceptor, thereby cooling a region of the rear side of the susceptor by means of the cooling gas, wherein the cooled region extends from the center of the susceptor radially outward, wherein the gas distributor head is embodied such that a ratio d/D is not less than 0.1 and not more than 0.4, wherein d denotes the diameter of the cooled region of the rear side of the susceptor and D denotes the diameter of the semiconductor wafer. |