摘要 |
Object of the present invention is to provide uniform heat distribution to a substrate undergoing heat treatment on top of a heat exchange plate. A heat exchange plate 1 is a flat, circular receptacle, has a cooling liquid inflow opening 11 on one end and outflow opening 13 on the other end, and cooling liquid flows on the inside. The surface of the plate 1 is divided, for example, into four zones having different heat capacities and heat transfer characteristics, and an independently controllable foil heater 21A, 23A, 25A, 27A is attached to each zone. Heater 21A covers a zone, which circumferentially surrounds a substrate placed on top of a plate, heater 23A covers a zone directly beneath a substrate, heater 25A covers a zone of the vicinity of the outflow opening 13, and heater 27A covers a zone of the vicinity of the inflow opening 11. Temperature sensors 31-33 are disposed on the inside of a plate at four locations of a second zone, which are apt to receive the affects of the first to fourth zones. Based on each plate temperature detected by the temperature sensors 31 to 33, a temperature of the substrate at a location corresponding thereto is estimated.
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