Measurex Corporation

Kasper Instruments, Inc.

Eaton Corporation

Tor G Larsen

Karl-Heinz Johannsmeier

Paul E Stoft

Pekka M Typpo

Gunnar Wennerberg

John J Howarth

David L Allen

An auto-focusing alignment and measurement system for use in precisely positioning a semiconductor substrate with respect to an integrated circuit mask is herein disclosed. This system includes a moveable convergent lens operable with another pair of convergent lenses for alternately focusing images of the mask and the substrate onto a photodiode array. The photodiode array serves as a focus detector and, together with associated signal processing circuitry, provides a feedback signal for controlling displacement of the moveable lens to equal the separation between the mask and the substrate with an accuracy better than the depth of field of the optics. An illumination source and viewing optics provide a magnified view of images of both the mask and the substrate superimposed and in focus, thereby facilitating alignment of the substrate with respect to the mask prior to photolithographic printing. This apparatus may also be employed to measure the degree of surface flatness and parallelism between the mask and the substrate and the dimensions of surface features.

Auto-focus alignment and measurement system and method

An auto-focusing alignment and measurement system for use in precisely positioning a semiconductor substrate with respect to an integrated circuit mask is herein disclosed. This system includes a moveable convergent lens operable with another pair of convergent lenses for alternately focusing images of the mask and the substrate onto a photodiode array. The photodiode array serves as a focus detector and, together with associated signal processing circuitry, provides a feedback signal for controlling displacement of the moveable lens to equal the separation between the mask and the substrate with an accuracy better than the depth of field of the optics. An illumination source and viewing optics provide a magnified view of images of both the mask and the substrate superimposed and in focus, thereby facilitating alignment of the substrate with respect to the mask prior to photolithographic printing. This apparatus may also be employed to measure the degree of surface flatness and parallelism between the mask and the substrate.

Auto focus alignment and measurement system and method

An apparatus for automatically aligning a semiconductor wafer with a mask in the manufacture of integrated circuit devices is disclosed. The mask and wafer are each provided with alignment patterns, the alignment pattern on the wafer cooperating with the alignment pattern on the mask in a unique visual mannner to signify alignment. A scanning mechanism is provided for automatically scanning the alignment pattern areas and producing output signals indicative of the relative positions of the alignment patterns on the wafer and mask. Logic circuitry is provided for operating in response to any misalignment represented by the scan output signals to compute formulae which are utilized to produce control signals for driving motor drive mechanisms to produce relative movement between the mask and wafer to bring them into alignment. Several separate alignment cycles are provided, if needed, for zeroing in on finalized alignment. A tolerance selection control circuit is provided for permitting a variation in final alignment tolerance.

Apparatus for the automatic alignment of two superimposed objects, e.g.

In an apparatus for the measurement of the thickness of a sheet through the use of air bearings, the apparatus has a stationary housing, a member in the housing capable of being extended in a direction substantially perpendicular to the sheet, and a fluid ring bearing capable of directing fluid to impinge the member in a substantially omnidirection which is substantially perpendicular to the direction of extension of the member.

Caliper gauge for the measurement of sheet members over a wide range of

An apparatus to measure select properties such as color, brightness or gloss, of a moving sheet, is insensitive to flutter in the sheet. The apparatus comprises a housing to one side of said sheet. A source is located in the housing; the source is capable of emitting a beam of electromagnetic radiation which is aligned to impinge the sheet. The radiation is selected such that it is capable of being absorbed and being reflected by the select properties of the sheet. A collector is also located in the housing; the collector is capable of receiving a portion of the beam reflected from the sheet. A detector capable of measuring the select properties of the sheet based upon the radiation received by the collector is also provided. The housing is held at a constant distance from the sheet by a stream of fluid from the housing directed to impinge the sheet in a direction substantially perpendicular to the sheet. A standardization member is to the other side of the sheet. The standardization member is also held at a constant distance from the sheet by a stream of fluid from the member directed to impinge the sheet along a direction substantially perpendicular to the sheet and in linear alignment with the stream of fluid from the housing.

Apparatus to measure select properties of a moving sheet

An apparatus for automatically aligning a semiconductor wafer with a mask in the manufacture of integrated circuit devices is disclosed. The mask and wafer are each provided with alignment patterns, the alignment pattern on the wafer cooperating with the alignment pattern on the mask in a unique visual manner to signify alignment. A scanning mechanism is provided for automatically scanning the alignment pattern areas and producing output signals indicative of the relative positions of the alignment patterns on the wafer and mask. Logic circuitry is provided for operating in response to any misalignment represented by the scan outout signals to compute formulae which are utilized to produce control signals for driving motor drive mechanisms to produce relative movement between the mask and wafer to bring them into alignment. Several separate alignment cycles are provided, if needed, for zeroing in on finalized alignment. A tolerance selection control circuit is provided for permitting a variation in final alignment tolerance.

Apparatus for the automatic alignment of two superimposed objects, for

A contacting caliper gauge measures the thickness of a sheet material moving from the anterior to the posterior of the gauge. The gauge has two matched heads, one to either side of the sheet. Each head has a base, a skid and a bellow. The skid is hinged to the anterior of the base and is between the base and the sheet. The other end of the skid is attached to a bellow. The bellow is also attached to the posterior of the base and is substantially perpendicular to the sheet. A cap is attached to the bellow. The cap has a surface parallel to the sheet near the posterior and rounded near the anterior. The two heads are positioned with the bellow of one in line with the bellow of the other. In a preferred embodiment, the gauge further comprises means for permitting the skid of each head to rotate about an axis which is substantially perpendicular to the hinge near the anterior of the base.

Contacting caliper gauge

A contacting caliper gauge measures the thickness of a sheet material moving from the anterior to the posterior of the gauge. The gauge has two matched heads, one to either side of the sheet. Each head has a base, a skid and a bellow. The skid is hinged to the anterior of the base and is between the base and the sheet. The other end of the skid is attached to a bellow. The bellow is also attached to the posterior of the base and is substantially perpendicular to the sheet. A cap is attached to the bellow. The cap has a surface parallel to the sheet near the posterior and beveled near the anterior. The two heads are positioned with the bellow of one in line with the bellow of the other.

An apparatus for automatically aligning a semiconductor wafer with a mask in the manufacture of integrated circuit devices is disclosed. The mask and wafer are each provided with alignment patterns, the alignment pattern on the wafer cooperating with the alignment pattern on the mask in a unique visual manner to signify alignment. A scanning mechanism is provided for automatically scanning the alignment pattern areas and producing output signals indicative of the relative positions of the alignment patterns on the wafer and mask. Logic circuitry is provided for operating in response to any misalignment represented by the scan output signals to compute formulae which are utilized to produce control signals for driving motor drive mechanisms to produce relative movement between the mask and wafer to bring them into alignment. Several separate alignment cycles are provided, if needed, for zeroing in on finalized alignment. A tolerance selection control circuit is provided for permitting a variation in final alignment tolerance.

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Saratoga, CA, United States of America

Tor G Larsen