Detection system and detection method capable of detecting ripple defects of quartz wafer
By designing a detection system including light source, coaxial imaging and light adjustment devices, the problem of difficult detection of corrugated defects in quartz wafers is solved, and defects on quartz wafers are revealed, which improves the yield of quartz chips.
Patent Information
- Application Number
- CN202410589533.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-23
- Filing Date
- 2024-05-13
- Publication Date
- 2025-03-25
AI Technical Summary
Corrugated defects may occur during the manufacturing process of quartz wafers, resulting in uneven etching rates, affecting chip performance and reducing yields, especially in thinner quartz chips.
A detection system is designed, including a light source device, a coaxial image pickup device and a light adjustment device. The illumination light is partially blocked by the light adjustment device, so that the illumination light forms obliquely incident and forward incident asymmetric light components after passing through the objective lens group, and corrugated defects on the quartz wafer are shown.
Effectively detect corrugated defects of quartz wafers, avoid defective wafers entering the subsequent process, and improve the yield of the overall process.
Smart Images
Figure CN119688713A_ABST
Abstract
Description
[Technical field]
[0001] The technical field of the present invention relates to an optical detection technology, and more specifically, the present invention relates to a detection system and a detection method capable of detecting waviness defects of a quartz wafer. [Background technology]
[0002] Quartz materials are used in various electronic products due to their inherent properties (e.g. low loss, small thermal expansion coefficient, piezoelectric effect, etc.). For example, quartz oscillators are widely used in communication products such as mobile phones and network equipment.
[0003] During the manufacturing process of quartz wafers, defects may occur when the lattice is formed. These defects can easily cause the manufactured quartz wafers to have ripple defects. Since the ripple defects will cause the etching rate of the quartz wafer to differ in all directions during the etching process, the performance of the manufactured quartz chip may be affected and fail to pass the inspection, which will lead to a reduction in yield. For quartz chips that are developing towards thinner shapes, the impact of ripple defects will become more significant, making the improvement of yield more challenging. [Summary of the invention]
[0004] In the detection system and detection method of some embodiments of the present invention, the ability to detect waviness defects in quartz wafers is provided.
[0005] In the detection system and detection method of some embodiments of the present invention, the problem that the ripple defects are difficult to detect is solved, thereby achieving the effect of improving the yield.
[0006] The quartz wafer is provided with the capability of detecting ripple defects, which enables the quartz wafer to be confirmed whether it has ripple defects before entering the subsequent various processes to produce various quartz chips, thereby preventing defective wafers from flowing into the later process and causing the end product yield to be reduced.
[0007] According to some embodiments of the present invention, a detection system capable of detecting corrugation defects of a quartz wafer is provided, and the detection system includes: a light source device, a coaxial imaging device, and a light adjustment device. The light source device is used to generate illumination light. The coaxial imaging device is used to receive the illumination light, and provide the illumination light to the quartz wafer in a coaxial illumination manner after passing through an objective lens group. The coaxial imaging device is also used to obtain a detection image of the quartz wafer. The light adjustment device is arranged between the light source device and the coaxial imaging device, and is used to provide partial shielding for the illumination light. Among them, the illumination light passing through the objective lens group becomes an oblique component that is incident on the quartz wafer obliquely and a forward component that is incident on the quartz wafer forwardly. The illumination light is defined with an axis, and the light adjustment device is used to make the oblique component appear asymmetric relative to the axis.
[0008] According to some embodiments of the present invention, the light adjustment device includes a blocking portion for blocking the illumination light and a light-transmitting portion for allowing the illumination light to pass through, and the area of the blocking portion can be configured to be larger than that of the light-transmitting portion.
[0009] According to some embodiments of the present invention, the illumination light of the incident light adjustment device defines a cross-sectional area on the axis through which the light passes, and the cross-sectional area is defined as four quadrants. The light adjustment device can be configured to provide shielding for at least two of the four quadrants of the cross-sectional area.
[0010] According to some embodiments of the present invention, the illumination light of the incident light adjustment device defines a cross-sectional area on the axis through which the light passes, and the cross-sectional area also defines four quadrants. The light adjustment device can be configured to provide shielding for three of the four quadrants of the cross-sectional area.
[0011] According to some embodiments of the present invention, the light adjusting device may be configured with a movable shielding element for selectively providing partial shielding for the illumination light incident on the light adjusting device.
[0012] According to some embodiments of the present invention, the shielding element may have two functional parts, one of which is used to allow all the illumination light of the incident light adjusting device to pass through, and the other functional part is used to partially shield the illumination light of the incident light adjusting device.
[0013] According to some embodiments of the present invention, another action portion is defined as a blocking portion that blocks the illumination light and a light-transmitting portion that allows the illumination light to pass, and the area of the blocking portion is larger than the light-transmitting portion. In addition, in some embodiments, the light-transmitting portion can be configured to have a fan-shaped opening with an opening angle less than or equal to 90 degrees.
[0014] According to some embodiments of the present invention, a method for detecting corrugation defects of a quartz wafer is provided, which is applied to a coaxial imaging device, and the coaxial imaging device is used to converge the illumination light to the quartz wafer after passing through the objective lens group for obtaining a detection image. The detection method is characterized in that: partial shielding is provided for the illumination light, so that the illumination light passing through the objective lens group becomes an oblique component of the oblique incident quartz wafer and a forward component of the forward incident quartz wafer, wherein the illumination light is defined to have an axis, and the oblique component is asymmetric relative to the axis.
[0015] In this way, by configuring the coaxial imaging device, under a specific detection environment (with specific lighting conditions), the corrugation defects on the quartz wafer can be displayed in the detection image. This allows the quartz wafer to be confirmed whether it has corrugation defects before entering the subsequent various processes to produce various quartz chips, thereby avoiding defective wafers from flowing into the later process, thereby improving the yield of the overall process.
Brief Description of the Drawings
[0016] Figure 1 is a schematic diagram of a quartz wafer inspection system according to some embodiments; Figure 2 is a partial schematic diagram of an illumination light on a light path according to some embodiments; Figure 3 is a schematic diagram of a light path of illumination light that is not partially shielded through an objective lens group according to some embodiments; Figure 4 is a schematic diagram of a light path of partially shielded illumination light passing through an objective lens assembly according to some embodiments; Figure 5 Based on Figure 3 Inspection image of quartz wafer obtained under illumination conditions (unshielded); Figure 6 Based on Figure 4 Inspection image of a quartz wafer obtained under the illumination condition of (the oblique component is asymmetric); Figure 7 The inspection image of the quartz wafer is obtained under the illumination condition that only the symmetrical oblique component of the illumination light is incident on the quartz wafer; Figure 8 is a schematic diagram of a light adjustment device according to a first embodiment; Fig. 9 is a schematic diagram of a light adjustment device according to a second embodiment; Fig.10 is a schematic diagram of a light adjustment device according to a third embodiment; Fig.11 FIG. 4 is a schematic diagram of a light adjustment device according to a fourth embodiment. [Specific implementation method]
[0017] In order to fully understand the purpose, features and effects of the present invention, the present invention is now described in detail with the help of the following specific embodiments and the accompanying drawings, as follows:
[0018] The coaxial imaging device can integrate the illumination light into the imaging path, that is, the coaxial imaging device makes the axis of the illumination light (e.g., the central axis) coaxial with the imaging axis, thereby providing illumination light to the object to be tested in a coaxial illumination manner, and then obtaining the detection image of the illuminated object to be tested. The coaxial imaging device is suitable for many detection environments that require uniform illumination and is widely used in various optical detection systems.
[0019] Please refer to Figure 1 , which is a schematic diagram of a quartz wafer detection system according to some embodiments. The detection system includes: a light source device 100, a coaxial imaging device 200 and a light adjustment device 300.
[0020] The light source device 100 is used to generate illumination light L1. The light adjustment device 300 is used to adjust the illumination light L1 generated by the light source device 100. The coaxial imaging device 200 receives the adjusted illumination light L2 and provides it to the quartz wafer 400 in a coaxial illumination manner. The coaxial imaging device 200 has an objective lens group 210, and the illumination light L2 forms an illumination light L3 that converges toward the quartz wafer 400 after passing through the objective lens group 210. In some other embodiments, the light adjustment device 300 can also be integrated into the coaxial imaging device 200 to achieve the same adjustment effect.
[0021] like Figure 1 As shown, the illumination light L1 generated by the light source device 100 is partially shielded based on the adjustment effect provided by the light adjustment device 300 to form an adjusted illumination light L2. After passing through the reflective element 201 and the beam splitter 202, the adjusted illumination light L2 provides illumination to the quartz wafer 400 on the imaging path of the imaging unit 220 to form a coaxial illumination condition. After passing through the objective lens group 210, the adjusted illumination light L2 forms a converged illumination light L3 for the quartz wafer 400. The reflected light LR of the illuminated quartz wafer 400 will enter the imaging unit 220 through the objective lens group 210 and the beam splitter 202 to generate a detection image. In some other embodiments, the reflective element 201 can also be omitted, for example: the light source device 100 is configured as a side-incident coaxial imaging device 200, and the illumination light L1 is generated to irradiate in the direction of the beam splitter 202.
[0022] Please refer to Figure 2, is a partial schematic diagram of the illumination light on the light path according to some embodiments. The illumination light L1 emitted from the light source device 100 can define a cross-sectional area A on any plane with the light path direction as the normal vector, such as a light spot formed on a physical plane. The illumination light L1 emitted from the light source device 100 can be defined by an axis C perpendicular to the plane to which the cross-sectional area A belongs, such as a central axis or the optical axis of the objective lens group 210. Axis C can be used as a comparison basis to show the relative shape (for example, symmetric or asymmetric) of the light irradiated toward the object to be tested. Figure 2 For example, the illumination light L1 emitted from the light source device 100 presents a symmetrical pattern relative to the axis C.
[0023] Please refer to Figure 3 and Figure 4 , Figure 3 is a schematic diagram of the light path of the illumination light that is not partially shielded through the objective lens group according to some embodiments, Figure 4 FIG. 1 is a schematic diagram of a light path of partially shielded illumination light passing through an objective lens assembly according to some embodiments. For ease of explanation, Figure 3 and Figure 4 The diagram is simplified, omitting the optical elements for reflection or light splitting that do not affect the light path converged to the quartz wafer 400. As for whether the illumination light is partially blocked, the difference between the two is represented by the amount of illumination light.
[0024] like Figure 3 As shown, the illumination lights L11, L12, and L13 emitted from the light source device 100 are not blocked. After passing through the objective lens group 210, they are respectively formed into corresponding parallel lights and converged onto the quartz wafer 400. The lights converged onto the quartz wafer 400 include the forward component L12' incident on the quartz wafer 400 in the forward direction and the oblique components L11' and L13' incident on the quartz wafer 400 in the oblique direction. Figure 3 It can be seen that after the illumination light that is not partially shielded passes through the objective lens assembly, relative to the axis C, no matter whether it is the normal component or the oblique component that enters the quartz wafer 400, it presents a symmetrical pattern.
[0025] like Figure 4 As shown, the illumination light L13 emitted from the light source device 100 is shielded (and therefore not shown in FIG. Figure 4 The remaining light beams, after passing through the objective lens group 210, form corresponding parallel light beams and converge onto the quartz wafer 400. The light beams converged onto the quartz wafer 400 include the forward component L12' incident on the quartz wafer 400 in the forward direction and the oblique component L11' incident on the quartz wafer 400 in the oblique direction. Figure 4It can be seen that after the remaining light passes through the objective lens assembly, the partially shielded illumination light has an oblique component incident on the quartz wafer 400 that is obviously asymmetric relative to the axis C (the oblique component L13 ′ is blocked and cannot enter the quartz wafer 400 ).
[0026] Please refer to Figure 5-Figure 7 , Figure 5 Based on Figure 3 Inspection image of quartz wafer obtained under the illumination condition (unshielded). Figure 6 Based on Figure 4 The inspection image of the quartz wafer obtained under the illumination condition (the oblique component is asymmetric). Figure 7 The inspection image of the quartz wafer is obtained under the illumination condition that only the symmetrical oblique component of the illumination light enters the quartz wafer (with Figure 3 To further illustrate, the illumination light L12 is blocked. The object used for observation is a quartz wafer with a corrugated defect. Figure 5-7 It can be seen that if the oblique component of the incident light on the quartz wafer 400 is asymmetric and the incident light on the quartz wafer 400 also has a forward component, the ripple defect will be clearly visible (such as Figure 6 shown), in addition, Figure 5 and Figure 7 Therefore, the oblique component of the incident light on the quartz wafer 400 must be asymmetrical, and at the same time, there must be a forward component to enable the inspection image to show the ripple defect. Figure 4 However, in some other embodiments, the forward component may also be configured as a symmetrical type.
[0027] Please refer to Figure 8 , is a schematic diagram of a light adjustment device of the first embodiment. The light adjustment device 300 includes a light-transmitting portion 310 and a blocking portion 320. The light-transmitting portion 310 is used to allow illumination light to pass through, for example, it is configured as a through hole or a light-transmitting element with a light transmittance higher than 90%. The blocking portion 320 is used to block the illumination light, for example, it is configured as an opaque element or a light-transmitting element with a light transmittance lower than 10%. The adjustment area 301 of the light adjustment device may correspond to, for example, Figure 2 The cross-sectional area A shown in the example. The area of the blocking portion 320 is configured to be larger than the area of the light-transmitting portion 310. Figure 8 In the example, there is a fan-shaped opening with an opening angle greater than 90 degrees.
[0028] Please refer to Fig. 9, which is a schematic diagram of the light adjustment device of the second embodiment. The illumination light L1 incident on the light adjustment device 300 defines a cross-sectional area A through which the light passes on the axis C. The cross-sectional area A also defines four quadrants, and the light adjustment device 300 is used to provide shielding for at least two of the four quadrants of the cross-sectional area A. Fig. 9 In the example shown, the light adjustment device 300 is used to shield three of the four quadrants of the cross-sectional area A (with the blocking portion 320), leaving only one quadrant (with the light-transmitting portion 310) to allow the remaining illumination light L1 to pass through. In addition, the light adjustment device 300 can also be configured to shield a larger area and leave only an area smaller than one quadrant to allow the remaining illumination light L1 to pass through. Fig. 9 In the example, there is a fan-shaped opening with an opening angle equal to 90 degrees.
[0029] Please refer to Fig.10 , is a schematic diagram of a light regulating device according to a third embodiment. The light regulating device 300 includes a movable shielding element 302. The shielding element 302 is provided with two action parts A1 and A2, the action part A1 is used to allow all the illumination light incident on the light regulating device 300 to pass through, and the action part A2 is used to partially shield the illumination light incident on the light regulating device 300. The movable shielding element 302 can provide operational flexibility, that is, it is operated to selectively arrange the action part A1 or the action part A2 on the light path area B according to the detection requirements, so as to adjust the illumination light incident on the light regulating device 300. Since such a detection system equipped with a coaxial imaging device can provide a variety of other detection functions at the same time, the movable shielding element 302 will provide greater flexibility and convenience in use for the detection system, and also achieve full utilization of the space occupied by the detection system.
[0030] The active portion A1 is defined with a light-transmitting portion 312 through which all the illumination light can pass. The active portion A2 is defined with a light-transmitting portion 311 (for example, configured as a through hole or a light-transmitting element with a light transmittance higher than 90%) through which most or all of the illumination light can pass, and a blocking portion 321 (for example, configured as an opaque element or a light-transmitting element with a light transmittance lower than 10%) through which most or all of the illumination light cannot pass. In addition, the light-transmitting portion 311 can be configured as a fan-shaped opening with an opening angle less than or equal to 90 degrees or at least less than 180 degrees. Fig.10 The illustrated light-transmitting portion 311 has a fan-shaped opening with an opening angle smaller than 90 degrees.
[0031] In the above-mentioned embodiments, the cross-sectional area A, the action part A1, and the action part A2 of the light spot are all exemplified by a circle (for example, the light source of the light source device 100 is provided by LEDs arranged in a circle). However, light sources forming light spots of other shapes can also be applied to the embodiments. In addition, relative to the axis C, the opening angle of each light-transmitting part (310, 311) can be selected according to the actual lighting requirements and the incident light source (light spot shape). When the light spot is circular or approximately circular in shape, the opening angle of the light-transmitting part (310, 311) can be configured to be at least less than 180 degrees when the oblique component of the incident light of the quartz wafer 400 is asymmetrically configured; on the other hand, when the light spot is not circular in shape, the size of the light-transmitting part (310, 311) can be configured according to the purpose of making the oblique component of the incident light of the quartz wafer 400 present an asymmetrical configuration.
[0032] Please refer to Fig.11 , which is a schematic diagram of the light adjustment device of the fourth embodiment. The illumination light L1 incident on the light adjustment device 300 defines a cross-sectional area A through which the light passes on the axis C. A fan-shaped area (i.e., the light-transmitting portion 310) with the axis as the vertex is defined in the cross-sectional area A. The light adjustment device 300 is used to provide shielding for the non-fan-shaped area in the cross-sectional area A. Fig. 9 In the embodiment of Fig.11 In the illustrated embodiment, the light adjustment device 300 can adjust the fan-shaped area (i.e., the light-transmitting portion 310) to cover the first and fourth quadrants at the same time in order to further improve the contrast of the defects, so as to allow the illumination light L1 of the fan-shaped area (i.e., the light-transmitting portion 310) to pass through and form the adjusted illumination light L2. In addition, the fan-shaped area (i.e., the light-transmitting portion 310) can be adjusted to cover the areas of other quadrants based on demand, that is, the fan-shaped area (i.e., the light-transmitting portion 310) can be rotated around the axis C as needed to obtain better image quality. The fan-shaped area (i.e., the light-transmitting portion 310) is Fig.11 In the example of , it is configured as a fan-shaped opening with an opening angle less than 90 degrees. In other embodiments centered on the axis C and with a circular light spot, the fan-shaped area (i.e., the light-transmitting portion 310) can be configured as a fan-shaped opening with an opening angle equal to 90 degrees or an opening angle at least less than 180 degrees.
[0033] Thus, the detection method for making the quartz wafer's corrugation defects visible mainly makes the illumination light converge onto the quartz wafer as the object to be detected after passing through the objective lens group, so as to obtain the detection image, and the method for making the quartz wafer's corrugation defects visible is to provide partial shielding for the illumination light. This shielding is to make the illumination light passing through the objective lens group include an oblique component that is incident on the quartz wafer obliquely and a forward component that is incident on the quartz wafer forwardly. In addition, the illumination light is defined with an axis, and the oblique component needs to present an asymmetric shape relative to the axis. In this way, the coaxial imaging device can be partially adjusted or modified on the existing detection system, so that the detection system can have the ability to detect the quartz wafer's corrugation defects.
[0034] In summary, the detection system and detection method disclosed in the embodiments, by configuring the coaxial imaging device, can make the corrugation defects on the quartz wafer appear in the detection image under a specific detection environment, thereby solving the problem that the corrugation defects are difficult to detect, thereby achieving the effect of improving the yield.
[0035] The present invention discloses preferred embodiments above, but those skilled in the art should understand that the embodiments herein are only used to describe the present invention and should not be interpreted as limiting the scope of the present invention. It should be noted that all changes and substitutions equivalent to the embodiments should be understood to be included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims. [Reference Signs]
[0036] 100 Light source device 200 Coaxial imaging device 201 Reflective element 202 Spectroscopic Element 210 Objective lens set 220 Image acquisition unit 300 Light adjustment device 301 Adjustment Zone 302 Shielding element 310 light-transmitting part 311 light-transmitting part 312 light-transmitting part 320 Blocking 321 Blocking Department 400 Quartz Wafer A Cross-sectional area A1 Action part A2 Action part B Light path area L1 Illumination light L11 illumination light L11' oblique component L12 Illumination light L12' positive component L13 Illumination light L13' oblique component L2 Illumination light L3 illumination light LR reflects light.
Claims
1. A detection system capable of detecting waviness defects of a quartz wafer, the detection system comprising: A light source device for generating an illumination light; a coaxial imaging device, used for receiving the illumination light and providing the illumination light to the quartz wafer in a coaxial illumination manner after passing through an objective lens group, and the coaxial imaging device is also used for obtaining a detection image of the quartz wafer; and a light adjustment device, disposed between the light source device and the coaxial imaging device, Among them, the illumination light passing through the objective lens group becomes an oblique component that is incident on the quartz wafer obliquely and a forward component that is incident on the quartz wafer forwardly, the illumination light defines an axis, and the light adjustment device is used to provide partial shielding for the illumination light so that the oblique component is asymmetric relative to the axis.
2. The detection system according to claim 1, wherein: The light adjustment device includes a blocking portion for blocking the illumination light and a light-transmitting portion for allowing the illumination light to pass through, and the area of the blocking portion is larger than that of the light-transmitting portion.
3. The detection system according to claim 1, wherein: The illumination light incident on the light adjustment device defines a cross-sectional area on the axis through which the light passes, and the cross-sectional area defines four quadrants. The light adjustment device is used to provide shielding for at least two of the four quadrants of the cross-sectional area.
4. The detection system according to claim 3, wherein: The light adjustment device is used to provide shielding for three of the four quadrants of the cross-sectional area.
5. The detection system according to claim 1, wherein: The light adjusting device comprises a movable shielding element for selectively providing partial shielding to the illumination light incident on the light adjusting device.
6. The detection system according to claim 5, wherein: The shielding element has two function parts, one of which is used to allow all the illumination light incident on the light adjustment device to pass through, and the other function part is used to partially shield the illumination light incident on the light adjustment device.
7. The detection system according to claim 6, wherein: The other action portion is defined as a blocking portion that blocks the illumination light and a light-transmitting portion that allows the illumination light to pass through, and the area of the blocking portion is larger than that of the light-transmitting portion.
8. The detection system according to claim 7, wherein: The light-transmitting portion is a fan-shaped opening with an opening angle less than or equal to 90 degrees.
9. A method for detecting corrugation defects of a quartz wafer, applied to a coaxial imaging device, wherein the coaxial imaging device is used to converge an illumination light onto the quartz wafer after passing through an objective lens group for obtaining a detection image, wherein the detection method is characterized in that: partial shielding is provided to the illumination light so that the illumination light passing through the objective lens group becomes an oblique component incident on the quartz wafer obliquely and a forward component incident on the quartz wafer forwardly, wherein: The illumination light defines an axis, and the oblique component is asymmetric with respect to the axis.
10. The detection method according to claim 9, wherein: The illumination light defines a cross-sectional area on the axis through which the light passes, and the cross-sectional area defines four quadrants. Partial shielding is provided to the illumination light by shielding at least two of the four quadrants.
11. The detection method according to claim 9, wherein: The illumination light defines a cross-sectional area on the axis through which the light passes, and the cross-sectional area defines four quadrants. Partial shielding is provided to the illumination light by shielding three of the four quadrants.
12. The detection method according to claim 9, wherein: The illumination light defines a cross-sectional area on the axis through which light passes, and the cross-sectional area defines four quadrants. The partial shielding provided to the illumination light is configured by allowing only light of a region smaller than one quadrant to pass through.
13. The detection method according to claim 9, wherein: The illumination light defines a cross-sectional area on the axis through which the light passes, and a fan-shaped area with the axis as the vertex is defined in the cross-sectional area. The illumination light is partially shielded by shielding areas other than the fan-shaped area.
14. The detection method according to claim 13, wherein: The fan-shaped area has a fan-shaped opening with an opening angle less than or equal to 90 degrees.