Surface topography measurement system and method

Abstract

This invention discloses a surface topography measurement system and method. The surface topography measurement method includes: a control module setting a synchronous scanning area and a skip scanning area for an object surface according to a scanning script; in the synchronous scanning area, an interferometer performs synchronous scanning at a first displacement speed, and a photographic device generates multiple interference images, the multiple interference images being associated with a reference light provided by the interferometer and multiple object-reflected lights reflected from the object surface; and in the skip scanning area, the interferometer first moves at a second displacement speed while the photographic device does not generate interference images, and then the interferometer performs synchronous scanning at the first displacement speed while the photographic device generates the interference images; wherein the second displacement speed is greater than the first displacement speed.

Claims

1. A surface topography measurement system, comprising: a light source for providing a test beam; an interferometer for splitting the test beam into a first sub-beam and a second sub-beam, the first sub-beam being incident on a reference mirror and reflecting a reference beam, the second sub-beam being incident on an object surface and reflecting multiple object-reflected beams, the object-reflected beams corresponding to different measurement heights of the interferometer along a first axis; a photographic device for receiving the reference beam and the object-reflected beams to selectively generate multiple interferometric images; and a control module electrically connected to the interferometer and the photographic device, configured according to a scan script to operate the interferometer and the photographic device in a first scan mode or a second scan mode; wherein in the first scan mode, the measurement height of the interferometer changes with a first displacement velocity and the photographic device records the interferometric images; wherein in the second scan mode, the measurement height of the interferometer changes with a second displacement velocity and the photographic device does not record the interferometric images, the second displacement velocity being greater than the first displacement velocity.

2. The surface topography measurement system as described in claim 1, wherein the scan script is associated with a current structure on the surface of the object, and when the scan script indicates that the current structure is a through hole edge or a raised structure edge, the control module sets the interferometer and the imaging device to operate sequentially in the second scan mode and the first scan mode.

3. The surface topography measurement system as described in claim 2, wherein when the scan script indicates that the current structure is not the edge of the through hole or the edge of the protruding structure, the control module sets the interferometer and the imaging device to operate in the first scan mode.

4. The surface topography measurement system as described in claim 2, wherein a jump time of the second scan mode is associated with the current structure indicated by the scan script.

5. The surface topography measurement system as described in claim 1, wherein the control module further configures the interferometer and the imaging device to operate in a third scanning mode to generate the scanning script, wherein in the third scanning mode, the interferometer moves along the first axis at a third displacement velocity and the imaging device records the interferometric images, the third displacement velocity being greater than the first displacement velocity.

6. The surface topography measurement system as described in claim 5, wherein each of the interferometric images is associated with the reference light and a corresponding interference fringe pattern of the object reflected light, and the control module determines the current structure based on the interferometric images generated by the third scanning mode.

7. The surface topography measurement system as claimed in claim 1, wherein the measurement height of the interferometer is associated with the position of the interferometer in a first axis, and the first displacement velocity or the second displacement velocity of the measurement height of the interferometer is the movement velocity of the interferometer in the first axis.

8. A surface topography measurement method for a surface topography measurement system, the system comprising an interferometer, a photographic device, and a control module, the method comprising: the control module setting a synchronous scanning region and a skip scanning region on a surface of an object according to a scanning script; in the synchronous scanning region, the interferometer performing synchronous scanning at a first displacement speed, and the photographic device generating multiple interference images, the interference images being associated with a reference light provided by the interferometer and multiple object-reflected lights reflected from the surface of the object; and in the skip scanning region, the interferometer first moving at a second displacement speed without the photographic device generating interference images, and then the interferometer performing synchronous scanning at the first displacement speed and the photographic device generating the interference images; wherein the second displacement speed is greater than the first displacement speed.

9. The surface topography measurement method as described in claim 8, wherein the interferometer performs synchronous scanning at the first displacement velocity so that when the interferometer provides the reference light and the reflected light from each of the objects, the photographic device synchronously generates one of the corresponding interferometric images.

10. The surface topography measurement method as described in claim 8, wherein the scan script is associated with a current structure on the surface of the object, and when the scan script indicates that the current structure is a through hole edge or a raised structure edge, the control module sets the through hole edge or the raised structure edge as the skip scan area.

11. The surface topography measurement method as described in claim 10, wherein when the scan script indicates that the current structure is the edge of the through hole or the edge of the protrusion structure, the interferometer performs a jump scan at a second displacement velocity with a jump time associated with a through hole depth or a protrusion height.

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