Shape measurement system, processing apparatus, shape measurement method, processing method, and chip manufacturing method

A processing apparatus which processes a workpiece, comprising:

• a holding unit which holds the workpiece;
• a processing unit which processes the workpiece;
• a measurement optical system which is disposed apart from the holding unit in a first direction;
• a moving unit which moves the measurement optical system and the holding unit relative to each other along a second direction crossing the first direction;
• and
• a controller which controls the moving unit,
• wherein the measurement optical system has
• a light source which emits low-coherence light,
• a splitting section which splits the light from the light source into reference light which is applied to a reference surface serving as a reflecting surface and measurement light which is applied to the workpiece,
• an objective lens which focuses the measurement light onto the workpiece, and
• a photoelectric conversion device which has a plurality of photoelectric conversion elements which receive interference light resulting from interference between the reference light reflected by the reference surface and the measurement light reflected by the workpiece, and
• when the moving unit causes the measurement optical system and the holding unit to move relative to each other along the second direction to scan the workpiece with the measurement light, an optical axis of the objective lens is inclined to the second direction at a predetermined angle.

A shape measurement method of measuring a three-dimensional shape of an object, comprising:

• applying, of low-coherence light which is split into reference light which is applied to a reference surface and measurement light which is applied to the object, the measurement light through an objective lens to the object held by a holding unit, and receiving interference light resulting from interference between the reference light reflected by the reference surface and the measurement light reflected by the object by a photoelectric conversion device;
• and
• changing a relative position between the photoelectric conversion device and the object held by the holding unit which are disposed apart from each other in a first direction, along a second direction crossing the first direction,
• wherein the three-dimensional shape of the object is measured by the receiving the interference light by the photoelectric conversion device and the changing the relative position between the photoelectric conversion device and the object in the second direction, and
• in the changing the relative position between the photoelectric conversion device and the object along the second direction, in a state in which an optical axis of the objective lens is inclined to the second direction at a predetermined angle, the photoelectric conversion device and the objective lens are moved relative to the holding unit along the second direction to scan the object with the measurement light.

A processing method of processing a workpiece, comprising:

• processing the workpiece by a processing unit to form a processing mark;
• after formation of the processing mark, applying, of low-coherence light which is split into reference light which is applied to a reference surface and measurement light which is applied to the processing mark, the measurement light to the processing mark of the workpiece held by a holding unit through an objective lens, and receiving interference light resulting from interference between the reference light reflected by the reference surface and the measurement light reflected by the processing mark by a photoelectric conversion device;
• and
• after formation of the processing mark, changing a relative position between the photoelectric conversion device and the processing mark of the workpiece held by the holding unit which are disposed apart from each other in a first direction, along a second direction crossing the first direction,
• wherein a three-dimensional shape of the processing mark is measured by the receiving the interference light by the photoelectric conversion device and the changing the relative position between the photoelectric conversion device and the processing mark along the second direction, and
• in the changing the relative position between the photoelectric conversion device and the processing mark along the second direction, in a state in which an optical axis of the objective lens is inclined to the second direction at a predetermined angle, the photoelectric conversion device and the objective lens are moved relative to the holding unit along the second direction to scan the processing mark with the measurement light.

A chip manufacturing method of manufacturing chips from a workpiece, comprising:

• processing the workpiece by a processing unit to form a processing groove portion having such a depth as not to fully cut the workpiece;
• after formation of the processing groove portion, measuring a three-dimensional shape of the processing groove portion;
• and
• after measurement of the three-dimensional shape of the processing groove portion, cutting the workpiece so as to pass through a bottom portion of the processing groove portion, to divide the workpiece into chips,
• wherein the measuring the three-dimensional shape of the processing groove portion includes
• applying, of low-coherence light which is split into reference light which is applied to a reference surface and measurement light which is applied to the processing groove portion, the measurement light to the processing groove portion of the workpiece held by a holding unit through an objective lens, and receiving interference light resulting from interference between the reference light reflected by the reference surface and the measurement light reflected by the processing groove portion by a photoelectric conversion device, and
• changing a relative position between the photoelectric conversion device and the processing groove portion of the workpiece held by the holding unit which are disposed apart from each other in a first direction, along a second direction crossing the first direction, and
• in the changing the relative position between the photoelectric conversion device and the processing groove portion of the workpiece held by the holding unit along the second direction, in a state in which an optical axis of the objective lens is inclined to the second direction at a predetermined angle, the photoelectric conversion device and the objective lens are moved relative to the holding unit along the second direction to scan the processing groove portion with the measurement light.

A chip manufacturing method of manufacturing chips from a workpiece, comprising:

• processing the workpiece by a processing unit and forming a processing groove portion which fully cuts the workpiece to divide the workpiece into chips;
• and
• after formation of the processing groove portion, measuring a three-dimensional shape of the processing groove portion,
• wherein the measuring the three-dimensional shape of the processing groove portion includes
• applying, of low-coherence light which is split into reference light which is applied to a reference surface and measurement light which is applied to the processing groove portion, the measurement light to the processing groove portion of the workpiece held by a holding unit through an objective lens, and receiving interference light resulting from interference between the reference light reflected by the reference surface and the measurement light reflected by the processing groove portion by a photoelectric conversion device, and
• changing a relative position between the photoelectric conversion device and the processing groove portion of the workpiece held by the holding unit which are disposed apart from each other in a first direction, along a second direction crossing the first direction, and
• in the changing the relative position between the photoelectric conversion device and the processing groove portion of the workpiece held by the holding unit along the second direction, in a state in which an optical axis of the objective lens is inclined to the second direction at a predetermined angle, the photoelectric conversion device and the objective lens are moved relative to the holding unit along the second direction to scan the processing groove portion with the measurement light.