公开(公告)号：US20010050938A1

公开(公告)日：2001-12-13

申请号：US09826301

申请日：2001-04-03

Applicant: Lambda Physik AG.

Inventor： Igor Bragin ,  Vadim Berger ,  Uwe Stamm ,  Ulrich Rebhan

IPC: H01S003/22 ,  H01S003/223

CPC classification number: H01S3/036 ,  H01S3/038 ,  H01S3/0971 ,  H01S3/225

Abstract: A laser for an excimer or molecular fluorine laser includes an electrode chamber connected with a gas flow vessel and having a pair of main electrodes and a preionization unit each connected to a discharge circuit. A spoiler is provided within the electrode chamber and is shaped to provide a more uniform gas flow through the discharge area between the main electrodes, to shield one of the preionization units from one of the main electrodes, and to reflect acoustic waves generated in the discharge area into the gas flow vessel for absorption therein. A spoiler unit may include a pair of opposed spoiler elements on either side of the discharge area. One or both main electrodes includes a base portion and a center portion which may be a nipple protruding from the base portion. The center portion substantially carries the periodic discharge current such that the discharge width is and may be significantly less than the width of the base portion. The curvatures of both main electrodes may conform to the curvature of the gas flow through the discharge chamber to further improve aerodynamic performance. A plurality of low inductive conducting ribs are connected to the grounded main electrode and shaped to provide a more uniform flow of gases through openings defined between adjacent ribs.

公开(公告)号：US20010040905A1

公开(公告)日：2001-11-15

申请号：US09891928

申请日：2001-06-25

Applicant: Lambda Physik AG

Inventor： Uwe Stamm ,  Hans-Stephan Albrecht ,  Uwe Leinhos ,  Wolfgang Zschocke

IPC: H01S003/13

CPC classification number: G01J1/58

Abstract: An ultraviolet light detection system is provided wherein a dark current background growth rate with total accumulated exposure dose is avoided, and parameters of an ultraviolet radiation source such as an ArF-excimer laser may be monitored without rapid degradation of the signal by the superposition of the dark current background over a desired signal. The invention provides a detector including a light sensitive element having a frequency conversion coating on its surface. The coating is preferably directly on the light sensitive element, absorbing incident ultraviolet light and re-emitting visible light in a direction toward the light sensitive element. The coating minimizes a dark current background that would otherwise appear when incident ultraviolet light impinges directly upon the light sensitive element, and thereby extends a lifetime of the light sensitive element. The detector is useful for detecting a wide range of ultraviolet wavelengths, and is particularly useful in solving the dark current growth rate with total accumulated exposure dose problem associated with detecting incident radiation under 240 nm.