US 6,647,632 B2 · Position measuring apparatus

Abstract

A position measuring apparatus for an alignment of an array of devices such as a thin film magnetic heads on a semiconductor wafer with a high degree of accuracy and satisfactory reproducibility, comprising, on a base, an object holding unit on which an object to be measured, an X-stage, a portal sub-base arranged across over the X-stage, a Y-stage arranged on the portal sub-base, a TV microscope (detector) capable of movement in a Z-axial direction, a ball circulation type linear guide and a motor for driving and guiding the X-stage and the Y-stage, an X-axial straight bar and a Y-axial straight bar attached to side surfaces of the object holding unit, and triangulation type laser displacement meters arranged in the vicinity of and in opposite to the X-axial bar and Y-axial bar, for detecting lateral motion errors during straight movement of the holding unit in the X- and Y-axial direction with a high degree of accuracy.

Claims12

Dependent claims

A position measuring apparatus for detecting a lateral variation during straight motion of a stage, comprising:

a base;
an object holding unit for holding thereon said object to be measured;
a first stage, on which said object holding unit is placed;
a first axial drive and guide unit for driving and guiding said first stage in a first axial direction;
an image detecting unit provided above said object holding unit, for picking up an image of said object so as to deliver an image signal thereof;
a first detection unit for detecting a lateral variation during straight motion of said first stage in said axial direction, said first detection unit provided in the vicinity of the side surface of said first axial direction of said object holding unit;
and
a compensating unit coupled with said first detection unit, for compensating said image signal outputted from said image detection unit on the basis of a signal from said first detection unit,
wherein said first detection unit comprises:
a plane reflector attached to a first axial side surface of said object holding unit, for reflecting laser light and a laser interferometer provided in the vicinity of and in opposite to said plane reflector.

7 more elements

A position measuring apparatus for detecting a lateral variation during straight motion of a stage, comprising;

a base;
an object holding unit for holding thereon an object to be measured;
a first stage, on which said object holding unit is placed, provided above said base, for moving said object holding unit in a first axial direction;
a sub-base arranged on said base and extended in a second axial direction orthogonal to said first axial direction;
a second stage adapted to move on said sub-base in said second direction;
a first and a second axial drive and guide unit for driving and guiding said first and second stages in a first and second axial direction, respectively;
an image detecting unit provided on said second stage, movable in a third axial direction orthogonal to said first stage, for picking up an image of said object to be measured so as to deliver an image signal thereof;
a first detection unit provided in the vicinity of a side surface of said first stage which extends in the first axial direction, for detecting a lateral variation during straight motion of said first stage in said first axial direction;
a second detection unit provided in the vicinity of a side surface of said second-stage which extends in the second axial direction, for detecting a lateral variation during straight motion of said second stage;
and
a compensating unit coupled with said first and second detection units, for compensating said image signal outputted from said image detection unit on the basis of signals outputted from the first and second detection units.

8 more elements

Dependencies are inferred from the claim text.

Position measuring apparatus

Life of this patent

Position measuring apparatus

Life of this patent

Abstract

Claims12