Patent ID: 6221166
Filing Date: 2001-04-24
Classification: C23C,H01L

Abstract:
A replaceable multi-thermal zone workpiece shielding plate apparatus for engaging a portion of the workpiece and shielding the engaged portion of the workpiece during processing thereof to prevent processing on the engaged portion of the workpiece in a high temperature processing system, the apparatus keeping the workpiece temperature hot at the shielded area and maintaining the rest of the shield cooler, the apparatus comprising:a) a replaceable shield of comparable weight as the workpiece for allowing replacement of the shield in the same way as the replacement of the workpiece;a) a low thermal transmitivity section in the portion of the shield to be engaged and shielding the workpiece, the low transmitivity section preventing the heat lost of the shielded portion of the hot workpiece due to less thermal energy transmitting through the shielding portion of the shield, thus maintaining a more uniform temperature at the shielded portion of the workpiece;b) a high thermal transmitivity section in the rest of shield, the portion of the shield not engaged with the workpiece having high thermal transmitivity to allow more thermal energy from the heater means and from the hot workpiece transmitting through the shield without heating the shield, thus maintaining a cooler temperature at the portion of the shield not engaged with the workpiece.