公开(公告)号：DE3169257D1

公开(公告)日：1985-04-18

申请号：DE3169257

申请日：1981-08-28

Applicant: IBM

Inventor： MAUER IV ,  MICHAIL MICHEL SALIB ,  WOODARD OLLIE CLIFTON

IPC: H01L21/027 ,  H01J37/147 ,  H01J37/317 ,  H01J37/30

公开(公告)号：DE2860511D1

公开(公告)日：1981-04-02

申请号：DE2860511

申请日：1978-12-22

Applicant: IBM

Inventor： DAVIS DONALD EUGENE ,  WEBER EDWARD VICTOR ,  WILLIAMS MAURICE CARMEN ,  WOODARD OLLIE CLIFTON

IPC: G01B15/00 ,  H01J37/304 ,  H01L21/027 ,  H01L21/302 ,  H01J37/30 ,  H01L21/66

Abstract: A method and apparatus is described for performing automatic overlay measurements on wafers utilized in semiconductor manufacturing. The overlay measurements are made at selected sites on a given wafer where a single bar pattern has been overlaid over a double bar pattern. The position of the single bar center line with respect to the center line between the double bars is a direct indication of the overlay error of the two patterns. The overlay error is measured in both the X and Y dimensions and is utilized to monitor the overlay error or to produce statistics and correlations to system parameters so that the sources of overlay errors may be identified and the errors eliminated or minimized on subsequent wafers being processed.

公开(公告)号：DE2441421A1

公开(公告)日：1975-03-13

申请号：DE2441421

申请日：1974-08-29

Applicant: IBM

Inventor： PFEIFFER HANS CHRISTIAN ,  WOODARD OLLIE CLIFTON

IPC: H01J37/147 ,  H01J37/244 ,  H01J37/304 ,  H01L21/027 ,  H01J3/26 ,  H01L21/26

Abstract: A square-shaped electron beam is stepped from one predetermined position to another to form a desired pattern on each chip of a semiconductor wafer to which the beam is applied. During various times, e.g., the target stage is moving mechanically from one chip to the next one, the electron beam is blanked. The blanking aperture plate in the electron beam column is provided with a second sensing aperture. During a blanked phase, the condensor lens images the electron source on the sensing aperture of the blanking aperture plate. A sensing plate disposed beneath the blanking aperture monitors the beam current and provides a signal to an alignment servo. Error correction is carried out by moving the beam in small increments in two orthogonal directions until the sensing plate reads a maximum current.

公开(公告)号：DE2332604A1

公开(公告)日：1974-01-24

申请号：DE2332604

申请日：1973-06-27

Applicant: IBM

Inventor： HALL ALAN VINCENT ,  WOODARD OLLIE CLIFTON

IPC: H01J37/06 ,  G05F1/46 ,  H01J9/227 ,  H01J37/24 ,  H01J37/304 ,  H03F17/00 ,  G05F1/50