PINHOLE DETECTOR FOR SUSCEPTOR AND DETECTING METHOD OF PINHOLE

摘要

PURPOSE:To simply and accurately detect pinhole of a susceptor on off-line and to reduce loss in the process of gas phase grow of semiconductor by allowing the susceptor to absorb and desorb He gas and observing the gas. CONSTITUTION:The susceptor 8 is held in a vacuum chamber 1, 1' (a two-pieces chamber), and the chamber 1, 1' is evacuated by evacuation system 5, 6. The susceptor 8 is evacuated while heated by a heater 2 for deaeration, and then cooled to room temp. The inner atmosphere in the vacuum chamber 1, 1' is replaced by He (V1) so that the susceptor 8 absorbs He, and then the chamber is purged with N2 (V2), and N2 is evacuated. Then the amt. of He is measured by a He detector 7 while the susceptor is evacuated and heated.