Adjustable polarization mechanism and optical detection device

Abstract

According to the adjustable polarization mechanism and the optical detection device, the polarizers with different polarization characteristics and the optical filters with different parameters are installed, the polarizers and the optical filters at different stations are transferred to an optical path through the driving component, switching of the polarizers and the optical filters can be rapidly completed, and the adjustment difficulty of optical elements is reduced. Meanwhile, the light shielding cover plate is arranged in the assembly of the optical detection device, the optical assembly can be cleaned or parts can be replaced at any time only by dismounting the light shielding cover plate, and the maintenance time is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer measurement, and in particular to an adjustable polarization mechanism and an optical detection device. Background Art

[0002] With the development of advanced semiconductor processes, the tolerance for wafer surface defects is getting lower and lower. Wafer surface defects mainly include scratches, particles, cracks, etc. These defects will have an adverse effect on subsequent chip manufacturing and reduce chip yield. In order to prevent wafers with surface defects from flowing into the subsequent production process, optical inspection is often used to check the surface quality of wafers. This method has the advantages of high precision, fast speed, and no pollution.

[0003] Although optical detection equipment has made great progress, the light collection device still has some shortcomings, such as the difficulty in adjusting optical components, the need to replace different polarization plates for light with different polarization characteristics, and the difficulty in quickly adapting to different detection needs. In addition, there are technical problems such as external light interference and difficulty in device maintenance. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes an adjustable polarization mechanism and an optical detection device, by setting polarizers with different polarization characteristics in the polarization mechanism and using an adjustment component to change different polarizers in the light path to quickly adapt to different optical detection requirements.

[0005] In order to achieve the above-mentioned purpose, the adjustable polarization mechanism of the present invention includes a polarization component, which includes a lens barrel seat and a driving component, wherein a plurality of polarizing film lens barrels are arranged in the lens barrel seat, and polarizing films with different polarization characteristics are installed in the polarizing film lens barrel; the above-mentioned driving component drives the lens barrel seat to move to transfer polarizing films at different positions to the optical path to meet different light polarization requirements.

[0006] In addition, when detecting wafer defects, a specific wavelength of detection light is required for surface defects of a certain size to improve the detection accuracy. At this time, a filter needs to be set on the optical path to allow the detection light that meets the wavelength requirement to pass. Preferably, the adjustable polarization mechanism of the present invention also includes a filter assembly, and the filter assembly includes a filter plate and a second driving component. The filter plate is also provided with a plurality of lens holes, and each lens hole is installed with a filter of different parameters to filter detection light of different wavelengths. The second driving component also drives the filter plate to move to transfer filters at different stations to the optical path.

[0007] Another object of the present invention is to provide an optical detection device, comprising the above-mentioned adjustable polarization mechanism.

[0008] The technical effects of the present invention are as follows: The adjustable polarization mechanism of the present invention is equipped with polarizers with different polarization characteristics, and the polarizers at different positions are transferred to the optical path by a driving component, so that the switching of the polarizers can be completed quickly. In addition, the filter assembly in the adjustable polarization mechanism is also driven by a second driving component to move the filter plate to transfer the filters at different positions to the optical path, so that the switching of the filters is completed quickly, so that the detection light that meets the wavelength requirements can pass. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural diagram of an optical detection device.

[0010] Figure 2 is a structural diagram of the polarization component.

[0011] Figure 3 This is a structural diagram of the polarization component without the light-shielding cover.

[0012] Figure 4 This is another perspective structural diagram of the polarization component without the shading cover.

[0013] Figure 5 This is the structural diagram of the cross roller guide.

[0014] Figure 6 It is a structural diagram of the filter component.

[0015] Figure 7 This is a structural diagram of the filter component without the shading cover.

[0016] Figure 8 is a structural diagram of the focusing component.

[0017] Fig. 9 is a structural diagram of the attenuation component.

[0018] Fig.10 This is a structural diagram of the attenuation component without the shading cover.

[0019] Fig.11 It is a structural diagram of the photoelectric conversion component.

[0020] Fig.12 This is a structural diagram of the lens assembly.

[0021] Fig.13 This is another perspective structural diagram of the lens assembly. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0023] Embodiment 1

[0024] See also Figure 1 An optical detection device includes a lens component 1, an adjustable polarization mechanism, a focusing component 4, an attenuation component 5 and a photoelectric conversion component 6 in sequence along the propagation direction of the light path, wherein the adjustable polarization mechanism includes a polarization component 2 and a filtering component 3.

[0025] Embodiment 2

[0026] An adjustable polarization mechanism, such as Figure 2-5 As shown, the polarization assembly 2 includes a polarization base 21, a driving component 22 and a lens barrel seat 23. A slide rail 24 is installed between the polarization base 21 and the lens barrel seat 23. The driving component 22 is installed on the polarization base 21. The driving component 22 drives the lens barrel seat 23 to move on the polarization base 21 along the slide rail 24. Three polarizing film barrels 25 are arranged on the lens barrel seat 23. Three polarizing film barrels 25 are installed with three polarizing films with different polarization characteristics. Preferably, no polarizing film is installed in one of the polarizing film barrels 25. A photoelectric sensor 26 is also installed on the polarization base 21 for detecting the specific position of the lens barrel seat 23.

[0027] Preferably, the driving component 22 is a servo screw motor; the slide rail 24 is two cross roller guide rails, a groove is provided on the bottom surface of the polarization base 21, the fixed part of the cross roller guide rail is installed in the above groove, and the sliding part is connected to the lens barrel seat 23. The servo screw motor drives the lens barrel seat 23 to slide relative to the polarization base 21, and the polarizers at different stations are switched into the light path. The top surface of the polarization base 21 is provided with a convex rib 211, a convex rib 212 and a convex rib 3 213, and the two ends of the servo screw motor are mounted on the convex rib 211 and the convex rib 212, and a light-transmitting hole 214 is provided on the polarization base 21 between the convex rib 212 and the convex rib 3 213.

[0028] The polarization component 2 also includes a shading cover 27, a shading cover 28 and a shading cover 3 29. The shading cover 27 is installed on the upper side of the polarization base 21, and the shading cover 28 and the shading cover 3 29 are installed on the lower side of the polarization base 21, wherein a light-transmitting hole 2 is provided at a position corresponding to the light-transmitting hole 33 on the light-transmitting cover 3 29. The shading cover 27, the shading cover 28 and the shading cover 3 29 are installed on the polarization base 21 to prevent ambient light from interfering with the detection.

[0029] like Figure 6-7As shown, the filter assembly 3 includes a filter base 31, a filter plate 32 and a second driving component 33. A second slide rail (not shown) is installed between the filter base 31 and the filter plate 32. The second driving component 33 is installed on the filter base 31. The second driving component 33 drives the filter plate 32 to move on the filter base 31 along the second slide rail. Two lens holes 35 are provided on the filter plate 32. Two filters with different parameters are installed in the two lens holes 35. Preferably, no filter is installed in one of the lens holes 35.

[0030] Preferably, the second driving component 33 is a cylinder, and a mounting plate 311 is provided at the end of the filter base 31, and the cylinder is mounted on the mounting plate 311. The cylinder is connected to the filter plate 32 through a floating joint 36, and a buffer 37 is also installed on the mounting plate 40, and one end of the buffer 37 abuts against the filter plate 32; the cylinder drives the filter plate 32 to slide relative to the filter base 31, and switches the filters at different stations into the optical path. The buffer 37 is used to reduce the impact of the cylinder on the filter plate 32 during the recovery process, and the floating joint 36 also reduces the impact of the cylinder on the filter plate 32.

[0031] The filter assembly 3 further includes a light shielding cover plate 4 38 and a light shielding cover plate 5 39, wherein the light shielding cover plate 4 38 and the light shielding cover plate 5 39 are mounted on the bottom surface of the filter base 31, a bottom plate is provided between the mounting plate 311, the light shielding cover plate 4 38 and the light shielding cover plate 5 39, and the light shielding cover plate 4 38 and the light shielding cover plate 5 39 are respectively connected to the convex rib 212 and the convex rib 3 213, so as to connect the filter assembly 3 with the polarization assembly 2. A convex rib 4 312 is further provided on the top surface of the filter base 31, and a light transmission hole 213 corresponding to the light transmission hole 214 is provided on the filter base 31 and the convex rib 4 312.

[0032] Embodiment 3

[0033] The specific structure of the focusing assembly 4 in the first embodiment is as follows: Figure 8 As shown, it includes a focusing component end plate 41, two focusing component side plates 42, a shading cover plate six 43, a mirror frame 44 and a focusing mirror 45. The focusing component end plate 41, the two focusing component side plates 42 and the shading cover plate six 43 form a space for installing the mirror frame 44, wherein the mirror frame 44 is installed on the focusing component end plate 41, and the focusing mirror 45 is installed on the mirror frame 44. The two focusing component side plates 42 are connected to the convex rib four 312, so as to connect the focusing component 4 with the filtering component 3 together.

[0034] Embodiment 4

[0035] The specific structure of the attenuation component 5 in the first embodiment is as follows: Figure 9-10As shown, the attenuation assembly bottom plate 51, the motor 52 and the attenuation sheet mounting wheel 53 are included, wherein the motor 52 is mounted on the top surface of the attenuation assembly bottom plate 51, the attenuation sheet mounting wheel 53 is mounted on the bottom surface of the attenuation assembly bottom plate 51, and the driving shaft of the motor 52 drives the attenuation sheet mounting wheel 53 to rotate. A plurality of attenuation sheet holes 54 are provided on the attenuation sheet mounting wheel 53, and five are provided in the fourth embodiment, and attenuation sheets with different parameters are respectively installed. Preferably, no attenuation sheet is installed in one of the attenuation sheet holes 54. A position sensor 55 is also installed on the bottom surface of the attenuation assembly bottom plate 51, which controls the motor 52 to drive the attenuation sheet mounting wheel 53 to rotate so as to switch the attenuation sheet in the optical path. The position of the attenuation sheet is fed back by the position sensor 55. Preferably, the position sensor 55 selects a photoelectric sensor.

[0036] A convex rib five 56 is provided on the top surface of the attenuation component base plate 51, a light-shielding shell 57 is installed on the bottom surface of the attenuation component base plate 51, a light-transmitting hole three corresponding to the light-transmitting hole two 313 is provided on the light-shielding shell 57, and a light-transmitting hole four 59 corresponding to the light-transmitting hole three 58 is provided on the attenuation component base plate 51 and the convex rib five 56.

[0037] Embodiment 5

[0038] The specific structure of the photoelectric conversion component 6 in the first embodiment is as follows: Fig.11 As shown, along the propagation direction of the light path, the optoelectronic conversion component seat 61, the aperture 62, the shutter 64 and the optoelectronic converter 65 are included in sequence. A servo motor 60 is installed on the top surface of the aperture 62. The servo motor 60 is used to control the size of the aperture light hole. The bottom end of the optoelectronic conversion component seat 61 is connected to the convex rib 56, connecting the optoelectronic conversion component 6 and the attenuation component 5 together.

[0039] Embodiment 6

[0040] The specific structure of the lens assembly 1 in the first embodiment is as follows: Figure 12-13 As shown, it includes a lens barrel 11 and a lens barrel adjustment device, the lens barrel adjustment device includes a fixed seat 12, an adjustment sleeve 13, an elastic connector 14 and an adjustment member, wherein the lens barrel 11 is connected to the adjustment sleeve 13; the adjustment sleeve 13 includes a cylinder 16 and an end plate 17, wherein the cylinder 16 extends into the fixed seat 12, the end plate 17 is located below the fixed seat 12, and an elastic connector 14 is provided between the fixed seat 12 and the end plate 17; the elastic connector 14 includes two rod bodies 141 and an elastic body 142 located between the rod bodies 141, wherein the rod bodies 141 are located in grooves on the backs of the fixed seat 12 and the end plate 17, and the elastic body 142 is located in through holes of the fixed seat 12 and the end plate 17. The adjustment member includes a plurality of tightening screws 18 screwed inside the fixed seat 12, preferably three, the heads of the tightening screws 18 abut against the outer wall of the cylinder 16, and the pitch angle of the lens barrel 11 can be adjusted by rotating the tightening screws 18.

[0041] The fixing seat 12 is connected to the light shielding cover plate 3 29 to connect the lens assembly 1 and the polarization assembly 2 together.

[0042] The components of the optical detection device include a light shielding cover plate. The optical components can be cleaned or parts can be replaced at any time by simply removing the light shielding plate, thereby reducing maintenance time.

[0043] The above describes in detail the basic principles, main features and advantages of the present invention in the field under investigation, and describes in detail some examples of use. Finally, it should be noted that the examples cited above are only used to explain this patent and are not used to limit the present invention. Although we have described the present invention in detail with reference to the examples, technicians in this field can still modify the examples and schemes described, or replace the relevant technical parts. Therefore, any modifications and equivalent replacements made within the spirit and principles of the present invention are within the scope of protection of the claims of the patent of this invention.

Claims

1. An adjustable polarization mechanism, comprising a polarization component, characterized in that: The polarization assembly includes a polarization base, a lens barrel seat and a driving component, a slide rail is installed between the polarization base and the lens barrel seat, the driving component is installed on the polarization base, and the driving component is connected to the lens barrel seat; a plurality of polarizing film barrels are arranged in the lens barrel seat, and polarizing films with different parameters are installed in the polarizing film barrel; the driving component drives the lens barrel seat to move so as to transfer polarizing films at different stations to the optical path.

2. An adjustable polarization mechanism as claimed in claim 1, characterized in that: The slide rails are two cross roller guide rails. A groove is provided on the bottom surface of the polarization base. The cross roller guide rails are respectively arranged on both sides of the groove. The fixed part of the cross roller guide rails is fixed in the groove. The sliding part of the cross roller guide rails is connected to the lens barrel seat.

3. An adjustable polarization mechanism as claimed in claim 1, characterized in that: The adjustable polarization mechanism also includes a filter assembly, which includes a filter base, a filter plate and a second driving component. A second slide rail is installed between the filter base and the filter plate. The second driving component is installed on the filter base and connected to the filter plate. A plurality of lens holes are provided in the filter plate, and filters with different parameters are installed in the lens holes. The second driving component drives the filter plate to move so as to transfer filters at different stations to the optical path.

4. An adjustable polarization mechanism as claimed in claim 3, characterized in that: The second driving component is a cylinder. A mounting plate is provided at the end of the filter base. The cylinder is mounted on the mounting plate. The cylinder is connected to the filter plate through a floating joint. A buffer is also installed on the mounting plate, and one end of the buffer abuts against the filter plate.

5. The adjustable polarization mechanism according to claim 3, characterized in that: The top surface of the polarization base is provided with convex rib 2 and convex rib 3, and a light-transmitting hole is provided on the polarization base between the convex rib 2 and convex rib 3; the filtering component also includes a light-shielding cover plate 4 and a light-shielding cover plate 5, and the light-shielding cover plate 4 and the light-shielding cover plate 5 are installed on the bottom surface of the filtering base, and the light-shielding cover plate 4 and the light-shielding cover plate 5 are respectively connected to the convex rib 2 and the convex rib 3; the polarization component also includes a light-shielding cover plate, a light-shielding cover plate 2 and a light-shielding cover plate 3, and the light-shielding cover plate is installed on the upper side of the polarization base, and the light-shielding cover plate 2 and the light-shielding cover plate 3 are installed on the lower side of the polarization base, and a light-transmitting hole 2 is provided on the light-shielding cover plate 3 at a position corresponding to the light-transmitting hole.

6. An optical detection device, characterized in that: It comprises the adjustable polarization mechanism as described in any one of claims 1 to 5, and comprises a lens assembly, an adjustable polarization mechanism and a photoelectric conversion assembly along the propagation direction of the light path.

7. An optical detection device as claimed in claim 6, characterized in that: The lens assembly includes a lens barrel and a lens barrel adjustment device, the lens barrel adjustment device includes a fixing seat, an adjustment sleeve, an elastic connector and an adjustment member; the lens barrel is connected to the adjustment sleeve; the adjustment sleeve includes a cylinder and an end plate, the cylinder extends into the fixing seat, and the end plate is located below the fixing seat; an elastic connector is provided between the fixing seat and the end plate, and an adjustment member is provided between the fixing seat and the adjustment sleeve.

8. An optical detection device as claimed in claim 7, characterized in that: The elastic connecting member comprises two rods and an elastic body located between the two rods, the rods are arranged in grooves on opposite sides of the fixing seat and the end plate, and the elastic body is located in through holes of the fixing seat and the end plate.

9. An optical detection device as claimed in claim 7, characterized in that: The adjusting member comprises a plurality of tightening screws screwed inside the fixing seat, and the heads of the tightening screws are in contact with the outer wall of the cylinder.

10. An optical detection device as claimed in claim 6, characterized in that: An attenuation component is also provided between the adjustable polarization mechanism and the photoelectric conversion component, and the attenuation component includes an attenuation component base plate, a motor and an attenuation plate mounting wheel; the motor is installed on the top surface of the attenuation component base plate, and the attenuation plate mounting wheel is installed on the bottom surface of the attenuation component base plate; the driving shaft of the motor drives the attenuation plate mounting wheel to rotate; the attenuation plate mounting wheel is provided with a plurality of attenuation plate holes, and attenuation plates with different parameters are installed in the attenuation plate holes.

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