Patent Number: 
Section: claims

1. A radiation detector having a radiation sensitive surface, said radiation-sensitive surface being sensitive for radiation with a wavelength between 10-200 nm, said radiation detector comprising:a silicon substrate having a surface area at a first surface side with a doping profile of a certain conduction type;a dopant layer provided on said first surface side of said silicon substrate, said dopant layer comprising a first layer of dopant material and a second layer, said second layer being a diffusion layer which is in contact with said surface area at said first surface side of the silicon substrate;a first electrode connected to said dopant layer;a second electrode connected to said silicon substrate;wherein said surface area at said first surface side of the silicon substrate and said second layer are arranged to form said radiation sensitive surface. 2. A radiation detector according to claim 1, wherein said certain conduction type is p-type conduction and said dopant material is a donor material. 3. A radiation detector according to claim 2, wherein said donor material comprises an element of a group of elements consisting of phosphorus, arsenic and antimony. 4. A radiation detector according to claim 1, wherein said certain conduction type is n-type conduction and said dopant material is an acceptor material. 5. A radiation detector according to claim 4, wherein said acceptor material comprises an element of a group of elements consisting of boron, gallium, aluminum and indium. 6. A radiation detector according to claim 4, wherein said first layer is a layer of Boron and said second layer is a layer of a BxSi1-x compound, x having a value between zero and one. 7. A radiation detector according to claim 6, wherein said second layer has a thickness of 1-10 nm. 8. A radiation detector according to claim 6, wherein said second layer has a thickness of 50-1000 nm. 9. A radiation detector according to claim 6, wherein said first layer has a thickness of 2-20 nm. 10. A radiation detector according to claim 1, wherein said silicon substrate comprises an epitaxial layer of crystalline silicon, and wherein the dopant layer has been provided on a surface of said epitaxial layer. 11. A radiation detector according to claim 1, wherein the first electrode partly covers said first layer of dopant material. 12. A radiation detector according to claim 11, wherein the first electrode is configured as a conductive grid. 13. A radiation detector according to claim 1, wherein the first electrode comprises one or more metallic materials selected from a group consisting of aluminum, titanium nitride, titanium, gold, nickel and chrome. 14. A radiation detector according to claim 1, wherein said silicon substrate further has a second surface side opposite to said first surface side and the second electrode is connected with said second surface side. 15. A radiation detector according to claim 1, wherein said radiation detector has a detector surface comprising first regions and second regions, said first regions being regions where said first layer is connected to said first electrode, and said second regions being regions where said first layer is covered with an isolation layer, said isolation layer being substantially transparent for said radiation. 16. A radiation detector according to claim 15, wherein said second regions have a cumulative surface area of 10-25 mm2. 17. A method of manufacturing a radiation detector comprising:providing a silicon substrate with a first surface side and a second surface side opposite thereto, wherein said silicon substrate has a surface area at said first surface side with a doping profile of a certain conduction type;depositing a layer of dopant material on top of the first surface of said silicon substrate such that in said silicon substrate a diffusion layer is formed;partly covering said layer of dopant material with a first contact layer comprising a metallic material such that first regions and second regions are formed, wherein the layer of dopant material is covered with said first contact layer in said first regions and remains exposed in said second regions;depositing a second contact layer comprising a metallic material at said second surface side of said silicon substrate. 18. A method according to claim 17, wherein the method after partly covering said layer of dopant material with a first contact layer further comprises covering said layer of dopant material in said second regions with an insulation layer, said insulation layer being substantially transparent for radiation with a wavelength between 10-200 nm. 19. A lithographic apparatus comprising:an illumination system configured to provide a beam of radiation;a support structure configured to support a patterning device that serves to impart said beam of radiation with a pattern in its cross-section;a substrate holder configured to hold a substrate in a substrate plane;a projection system configured to expose said patterned beam on said substrate;wherein said lithographic apparatus further comprises a radiation detector according to a radiation detector having a radiation sensitive surface, said radiation-sensitive surface being sensitive for radiation with a wavelength between 10-200 nm, said radiation detector comprising:a silicon substrate having a surface area at a first surface side with a doping profile of a certain conduction type;a dopant layer provided on said first surface side of said silicon substrate, said dopant layer comprising a first layer of dopant material and a second layer, said second layer being a diffusion layer which is in contact with said surface area at said first surface side of the silicon substrate;a first electrode connected to said dopant layer;a second electrode connected to said silicon substrate;wherein said surface area at said first surface side of the silicon substrate and said second layer are arranged to form said radiation sensitive surface substantially positioned in said substrate plane.