Method for inspecting a reticle, a method for manufacturing a reticle, and a method for manufacturing a semiconductor device using the same
A method for inspecting a reticle including a reflective layer on a reticle substrate is provided. The method may include loading the reticle on a stage, cooling the reticle substrate to a temperature lower than a room temperature, irradiating a laser beam to the reflective layer on the reticle substrate, receiving the laser beam using a photodetector to obtain an image of the reflective layer, and detect a particle defect on the reflective layer or a void defect in the reflective layer based on the image of the reflective layer.
1. A method for inspecting a reticle, the method comprising:
loading the reticle on a stage, the reticle including a reticle substrate and a reflective layer on the reticle substrate;
cooling the reticle substrate;
irradiating a laser beam to the reflective layer on the reticle substrate;
receiving the laser beam using a photodetector to obtain an image of the reflective layer; and
detecting whether a particle defect exists on the reflective layer or a void defect exists in the reflective layer based on the image of the reflective layer, wherein
the reticle substrate is cooled below 145 kelvins (K) to decrease a specific heat capacity of the reflective layer and to increase a power of the laser beam.
2. The method of claim 1 , wherein the laser beam has power of 0.87 W/cm 2 .
3. The method of claim 1 , wherein the laser beam includes ArF ultraviolet light.
4. The method of claim 1 , wherein the laser beam is scanned at a speed of 12.3 mm/s.
5. The method of claim 1 , wherein the reticle includes an extreme ultraviolet (EUV) reticle.
6. The method of claim 5 , wherein the reflective layer of the EUV reticle includes a molybdenum layer on a silicon layer.
7. The method of claim 5 , wherein the EUV reticle further includes an absorption pattern on the reflective layer.
8. The method of claim 1 , wherein the stage includes a cooler for cooling the reticle substrate.
9. The method of claim 8 , wherein the cooler includes a Peltier device or an air blowing device.