CAP FOR VERTICAL DIFFUSING FURNACE

摘要

PROBLEM TO BE SOLVED: To provide a cap for a vertical diffusing furnace which supports a boat in this furnace and has an integrated structure for holding it at an adequate temp. SOLUTION: A cap comprises a first flat plate 31, a second flat plate parallel distant from a film plate 31, support rods 33 which couple the first plate 31 with a second one 32 and heat insulated plates 34 which are disposed between the first and the second plates 31, 32 and contacted with the rods 33 at their outer surfaces. The plates 31, 32, 34 and rods 33 are integrated into a unit to prevent the process instability due to contaminant grains produced at parts assembling and facilitate installing and replacing the diffusion furnace.