公开(公告)号：US20040146295A1

公开(公告)日：2004-07-29

申请号：US10345097

申请日：2003-01-15

Applicant: NEGEVTECH LTD.

Inventor： Dov Furman ,  Gad Neumann ,  Mark Wagner ,  Noam Dotan ,  Ram Segal ,  Shai Silberstein

IPC: H04B010/08

CPC classification number: G01N21/9501 ,  G01N21/8806 ,  G01N21/95607 ,  G01N21/95623 ,  G01N2021/479 ,  G01N2021/8825 ,  G01N2201/0697 ,  G01N2201/0826

Abstract: Fast on-line electro-optical detection of wafer defects by illuminating with a short light pulse from a repetitively pulsed laser, a section of the wafer while it is moved across the field of view of an imaging system, and imaging the moving wafer onto a focal plane assembly, optically forming a continuous surface of photo-detectors at the focal plane of the optical imaging system. The continuously moving wafer is illuminated by a laser pulse of duration significantly shorter than the pixel dwell time, such that there is effectively no image smear during the wafer motion. The laser pulse has sufficient energy and brightness to impart the necessary illumination to each sequentially inspected field of view required for creating an image of the inspected wafer die. A novel fiber optical illumination delivery system, which is effective in reducing the effects of source coherence is described. Other novel aspects of the system include a system for compensating for variations in the pulse energy of a Q-switched laser output, methods for autofocussing of the wafer imaging system, and novel methods for removal of repetitive features of the image by means of Fourier plane filtering, to enable easier detection of wafer defects.

公开(公告)号：US20040136665A1

公开(公告)日：2004-07-15

申请号：US10345096

申请日：2003-01-15

Applicant: NEGEVTECH LTD.

Inventor： Dov Furman ,  Gad Neumann ,  Noam Dotan

IPC: G02B006/04

CPC classification number: G02B6/4298 ,  G01N21/9501 ,  G01N2021/479 ,  G02B6/04 ,  G02B6/4206 ,  G02B27/48

Abstract: A fiber optical illumination delivery system, which is effective in reducing the effects of source coherence. The system preferably utilizes either a single bundle of optical fibers, or serial bundles of optical fibers. In the single bundle embodiment, the differences in optical lengths between different fibers of the bundle is preferably made to be equal to even less than the coherence length of the source illumination. In the serial bundle embodiment, the fibers in the other bundle are arranged as groups of fibers of the same length, and it is the difference in lengths of these groups which is made equal to, or even more preferably, less than the overall difference in length between the shortest and the longest fibers in the other bundle. Both of these fiber systems enable construction of illumination systems delivering a higher level of illumination, but without greatly affecting the coherence breaking abilities of the system, thus enabling a generally more applicable system to be constructed.

Abstract translation: 一种光纤照明传输系统，可有效减少源相干的影响。 系统优选地使用单束光纤或串联的光纤束。 在单束实施例中，束的不同光纤之间的光学长度差异优选地等于甚至小于源照明的相干长度。 在串联捆绑实施例中，另一束中的纤维被布置成具有相同长度的纤维组，并且这些组的长度差异等于或甚至更优选地小于总体差异 另一束中最短和最长纤维之间的长度。 这两种光纤系统能够实现提供更高水平的照明的照明系统的构造，但是不会非常影响系统的相干断裂能力，从而能够构建一般更适用的系统。