摘要:
In a CVD apparatus, an epitaxial apparatus or an etching apparatus, the processing conditions are made uniform in a batch process by changing, with time, positions which are disposed in the direction of a gas flow in a reaction vessel and at which the optimal surface processing conditions are attained. By doing so, homogeneous and uniform films can be formed with a large substrate processing apparatus.
摘要:
A semiconductor wafer boat used in a vertical CVD apparatus includes four columns fixed to upper and lower support plates. Each of the columns has a plurality of first grooves arranged at regular intervals in the vertical direction so as to place wafers in substantially parallel to each other, and a plurality of second grooves formed alternately with the first grooves. A plate ring is provided for each of the second grooves so as to improve the uniformity of thickness of a film to be formed on each wafer. Each ring has an outer diameter larger than that of a wafer, and an inner diameter smaller than that of the wafer. Each ring is placed such that there is a clearance for transferring each wafer between each ring and each wafer in the vertical direction.