Claims
- 1. A detector for detecting extreme ultraviolet (EUV) radiation that comprises:a. an EUV sensitive photodiode having a diode active area that generates a current responsive only to EUV radiation; b. one or more mirrors that reflect EUV radiation having a defined wavelength(s) to the diode active area; c. a mask defining a pinhole that is positioned above the diode active area, wherein EUV radiation, is imaged through the pinhole; and d. an amplifier that is responsive to the current generated by the diode active area.
- 2. The detector of claim 1 further comprising means for directing ELJV radiation toward the one or more mirrors.
- 3. The detector of claim 1 wherein the detector comprises a housing assembly that has:a. a chamber in which the EUV sensitive photodiode is positioned; and b. an entrance through which EUV radiation enters the chamber.
- 4. The detector of claim 3 wherein the housing assembly comprises an elongated member having a bore through which EUV radiation enters the chamber.
- 5. The detector of claim 4 wherein the bore has a cross sectional area of from about 0.2 cm2 to 0.55 cm2.
- 6. The detector of claim 1 wherein the diode active area is coated with an EUV-transmissive energy filter.
- 7. The detector of claim 6 wherein the EUV-transmissive energy filter comprises zirconium.
- 8. The detector of claim 6 wherein the EUV-transmissive energy filter comprises a bandpass filter.
- 9. The detector of claim 1 wherein each of the one or more mirrors comprises a multilayer film comprises alternating layers of a first material having a refractive index and a second material having a refractive index that is larger than that of the first material.
- 10. The detector of claim 9, wherein the multilayer film comprises about 10 to 200 layer pairs.
- 11. The detector of claim 10 wherein the layer pairs have a periodicity of about 2 nm to 100 nm.
- 12. The detector of claim 1 wherein each of the one or more mirrors comprises a multilayer film comprising alternating layers of molybdenum and silicon.
- 13. The detector of claim 1 wherein the pinhole has an area of from about 0.03 mm2 to 0.13 mm2.
- 14. The detector of claim 1 wherein the diode active area has an area of about 1 mm2 to 4 mm2.
- 15. A method of measuring EUV radiation intensity in a system that includes a source of EUV radiation that comprises the steps of:a. providing a detector that comprises: i. an EUV sensitive photodiode having a diode active area that generates a current responsive to EUV radiation; ii. one or more mirrors that reflect EUV radiation having a defined wavelength(s) to the diode active area; iii. a mask defining a pinhole that is positioned above the diode active area, wherein EUV radiation passing through the pinhole is restricted substantially to illuminating the diode active area; and iv. an amplifier that is responsive to the current generated by the diode active area; b. positioning the detector within the system so that the EUV radiation passes through the pinhole of the mask and illuminates the diode active area.
- 16. The method of claim 15 wherein the detector generates a signal corresponding to the intensity of the EUV radiation from the source.
- 17. The method of claim 15 wherein the detector includes means for directing EUV radiation toward the one or more mirrors.
- 18. The method of claim 15, where the detector comprises a housing assembly that has:a. a chamber in which the EUV sensitive photodiode is positioned; and b. an entrance through which EUV radiation enters the chamber.
- 19. The method of claim 15 wherein the source of EUV radiation is a laser-produced plasma source.
Government Interests
This invention was made with Government support under Contract No. DE-AC04-94-AL85000 awarded by the U.S. Department of Energy to Sandia Corporation. The Government has certain rights to the invention.
US Referenced Citations (6)