Patent ID: 10642163

Abstract:
A system and method for controlling an exposure dose of a light source are disclosed. The system includes an LED light source, a light homogenizer, an energy detection unit and an exposure dose control unit coupled to both the LED light source and the energy detection unit. The energy detection unit includes an energy detector corresponding to the LED light source or the light homogenizer and an energy spot sensor corresponding to a wafer. By using the LED light source capable of producing UV light in lieu of an existing mercury lamp, the system is less hazardous and safer by eliminating the risk of discharging hazardous mercury vapor into the environment when the mercury lamp is broken. Moreover, exposure illuminance of the LED light source can be adjusted and the LED light source can be turned on/off under the control of exposure dose control unit to expose the wafer with high dose control accuracy, without needing to use a variable attenuator or an exposure shutter. This reduces the system's complexity and cost and increases its reliability.