A REFLECTANCE MEASUREMENT SYSTEM OF EUV PHOTOLITHOGRAPHY APPARATUS

摘要

PURPOSE: A reflectance measurement system of an extremely ultra-violet light(EUV) photolithography machine is provided to optimize an EUV photolithography process by obtaining accurate information related to light. CONSTITUTION: Light source generates the light in an EUV wavelength region. Relay mirrors(20b, 20c) collect and transmit the light from the light source. A photo-mask mirror(30) receives and reflects the light from the relay mirrors. A first light receiving unit is arranged on a light path from the photo-mask mirror and collects the light. A reflective mirror system receives the light from the photo-mask mirror. A second light receiving unit(60) collects the light from the reflective mirror system.