Semiconductor structure for detecting interdigital spacing
By measuring the capacitance value of the interdigital electrodes in a semiconductor structure, the problem of insufficient measurement accuracy of interdigital spacing in existing technologies is solved, enabling rapid and accurate monitoring and anomaly detection of MEMS devices, and improving product quality.
Patent Information
- Application Number
- CN202423152678.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2034-12-19
AI Technical Summary
Existing methods for measuring spacing have poor accuracy for interdigitated structures and cannot detect process abnormalities in a timely manner.
A semiconductor structure is designed, including a conductive layer, MEMS devices, and a connection structure. By applying a voltage to the contact structure to measure the capacitance between the interdigital electrodes, and combining the inverse relationship between the capacitance and the spacing, the change in the interdigital spacing can be accurately monitored.
This enables rapid and accurate measurement of the interdigital spacing, improves the accuracy of process anomaly monitoring, and ensures the yield and reliability of MEMS devices.
Smart Images
Figure CN223866364U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of semiconductor, concretely relates to a semiconductor structure of detection interdigital distance. BACKGROUND
[0002] Microelectromechanical system (MEMS) is a typical system of integrated sensor, micro-actuator and micro-circuit, which has been widely used in many fields such as automobile, aerospace, biological medicine and military. The goal of MEMS testing key technology is to establish a complete test system to evaluate the performance indicators of MEMS devices comprehensively, and to ensure its reliability and consistency.
[0003] However, the existing distance measurement method only measures the surface distance of the interdigital structure, and the precision is poor, and the process abnormality cannot be found in time. UTILITY MODEL CONTENT
[0004] The utility model solves the problem that the existing distance measurement method has poor precision.
[0005] To solve the above problems, the utility model provides a semiconductor structure for detecting interdigital distance, which comprises:
[0006] A first substrate;
[0007] A conductive layer is arranged on one side of the first substrate, and the conductive layer is provided with a pad structure and a contact structure arranged for electrical connection;
[0008] A MEMS device is arranged on the side of the conductive layer away from the first substrate, and the MEMS device comprises a plurality of interdigital electrodes and a connecting structure connected with the plurality of interdigital electrodes;
[0009] The connecting structure is connected with the pad structure, and when a voltage is applied to the contact structure, the distance between the plurality of interdigital electrodes in the MEMS device is determined by the capacitance value.
[0010] Optionally, the conductive layer comprises a first part and a second part arranged with insulation, the pad structure comprises a first pad structure and a second pad structure, the contact structure comprises a first contact structure and a second contact structure, the first pad structure and the first contact structure are arranged on the first part with mutual spacing, and the second pad structure and the second contact structure are arranged on the second part with mutual spacing.
[0011] Technical effects: The first pad structure and the second pad structure arranged in insulation enable both ends of the plurality of interdigital electrodes to simulate two poles of a capacitor. When a voltage is applied to the mutually insulated first contact structure and the second contact structure, the first contact structure and the second contact structure provide a power supply, and the distance between the plurality of interdigital electrodes can be determined by measuring the capacitance value of the capacitor formed by the plurality of interdigital electrodes.
[0012] Optionally, the first substrate includes a bearing area where the MEMS device is arranged and a non-bearing area surrounding the bearing area, the first pad structure and the second pad structure are respectively located at two end regions of the bearing area, and the connecting structure includes a first connecting structure and a second connecting structure, the first connecting structure is arranged on a side of the first pad structure away from the first substrate, and the second connecting structure is arranged on a side of the second pad structure away from the first substrate.
[0013] Technical effects: The first connecting structure connects the first pad structure and one end of the MEMS device, and the second connecting structure connects the second pad structure and the other end of the MEMS device, so that the MEMS device is in conduction with the contact structure, and the distance between the plurality of interdigital electrodes can be measured.
[0014] Optionally, the conductive layer further includes a first dielectric layer, the first dielectric layer is arranged in a middle region of the bearing area and connects the first part and the second part, and the first dielectric layer, the first connecting structure, the second connecting structure, the first pad structure and the second pad structure connect to surround the first cavity required for operation of the plurality of interdigital electrodes.
[0015] Technical effects: The first dielectric layer can effectively electrically isolate the first part and the second part, and the first dielectric layer, the first connecting structure, the second connecting structure, the first pad structure and the second pad structure are connected to surround the first cavity, so that higher integration can be achieved in a limited space.
[0016] Optionally, the first contact structure and the second contact structure are located in the non-bearing area.
[0017] Technical effects: By locating the first contact structure and the second contact structure in the non-bearing area, the function of the external power supply can be realized through the first contact structure and the second contact structure in subsequent packaging and manufacturing.
[0018] Optionally, the capacitance value is inversely proportional to the distance between the plurality of interdigital electrodes.
[0019] Optionally, the pad structure and the contact structure are integrally formed.
[0020] Technical effects: through the one-piece setting, the connection between the pad structure and the contact structure can be more closely, the joint and the complex node are reduced, the overall strength and stability are improved, and through the one-piece design, the manufacturing process can be simplified, the processing procedures and the waiting time are reduced, and the production efficiency is improved.
[0021] Optionally, the conductive layer is provided with a plurality of pad structures and a plurality of contact structures, and one pad structure and one contact structure are provided correspondingly.
[0022] The semiconductor structure comprises a plurality of MEMS devices, and one MEMS device is provided correspondingly with one pad structure.
[0023] Technical effects: through the one-to-one correspondence between each MEMS device and the pad structure, it can be ensured that each MEMS device can monitor the interdigital distance of the MEMS device through the contact structure, and then the interdigital distance of a plurality of MEMS devices can be detected in real time respectively, which helps to find and repair potential abnormalities in time, and improves the qualification rate and reliability of the MEMS device.
[0024] Optionally, the semiconductor structure further comprises:
[0025] The second substrate is provided with a groove, and the second substrate is connected with the MEMS device to enclose a second cavity required for the operation of the plurality of interdigital electrodes.
[0026] Optionally, the semiconductor structure further comprises: a second dielectric layer, which is arranged on the side of the MEMS device away from the first substrate, and is used for bonding the MEMS device and the second substrate.
[0027] The semiconductor structure for detecting the interdigital distance provided by the embodiment of the application is provided with a pad structure and a contact structure on the conductive layer, the pad structure is connected with the connecting structure of the MEMS device, the voltage is applied on the contact structure, the capacitance value between a plurality of interdigital electrodes can be measured quickly and accurately, and the change of the distance between the plurality of interdigital electrodes can be accurately determined according to the change of the capacitance value, so that the change of the distance of the whole interdigital electrode is accurately monitored, and the accuracy of the process abnormality monitoring is improved. BRIEF DESCRIPTION OF DRAWINGS
[0028] Figure 1 The structure schematic diagram of the semiconductor structure provided by the embodiment of the application is shown in the figure.
[0029] Figure 2 The structure schematic diagram of the semiconductor structure provided by the embodiment of the application is shown in the figure. Figure 1 The cross-sectional schematic diagram of the semiconductor structure is shown in the figure.
[0030] Explanation of reference signs:
[0031] 1. semiconductor structure; 11. first substrate; 12. conductive layer; 13. MEMS device; 15. pad structure; 14. contact structure; 16. second substrate; 17. second dielectric layer; 18. third dielectric layer;
[0032] 121. first part; 122. second part;
[0033] 131. interdigital electrode; 132. connecting structure; 133. first dielectric layer;
[0034] 151. first pad structure; 152. second pad structure;
[0035] 141. first contact structure; 142. second contact structure;
[0036] 1321. first connecting structure; 1322. second connecting structure. DETAILED DESCRIPTION
[0037] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below.
[0038] Please refer to Figure 1 and Figure 2 , Figure 1 The structure diagram of the semiconductor structure provided by the embodiment of the present application is shown in the figure, Figure 2 is Figure 1 The cross-sectional schematic diagram of the semiconductor structure is shown in the figure. The semiconductor structure 1 provided by the embodiment of the present application detects the interdigital distance, which includes a first substrate 11, a conductive layer 12 and a MEMS device 13. The conductive layer 12 is arranged on one side of the first substrate 11, and the conductive layer 12 is provided with a pad structure 15 and a contact structure 14 arranged for electrical connection. The MEMS device 13 is arranged on the side of the conductive layer 12 away from the first substrate 11, and the MEMS device 13 includes a plurality of interdigital electrodes 131 and a connecting structure 132 connected with the plurality of interdigital electrodes 131. Wherein, the connecting structure 132 is connected with the pad structure 15, and when the voltage is applied on the contact structure 14, the distance between the plurality of interdigital electrodes 131 in the MEMS device 13 is determined by the capacitance value. The embodiment of the present application can quickly and accurately measure the capacitance value between the plurality of interdigital electrodes 131 by applying voltage on the contact structure 14, and accurately determine the distance change between the plurality of interdigital electrodes 131 according to the change of the capacitance value, so as to accurately monitor the distance change of the whole interdigital electrode and improve the accuracy of the process abnormality monitoring.
[0039] Wherein, the voltage applied on the contact structure 14 can be applied by contacting the probe with the contact structure 14.
[0040] It should be noted that the capacitance value is inversely proportional to the spacing between the plurality of interdigital electrodes 131. Specifically, from formula 1: C=k*E0 A / d CD (n-1) to obtain the relationship between the spacing and the capacitance value, i.e. d CD = [k*E0 A (n-1)] / C.
[0041] E0 is the dielectric constant of vacuum;
[0042] n is the number of interdigital electrodes;
[0043] d CD is the relative spacing of the interdigital electrodes;
[0044] A is the relative area between the two interdigital electrodes;
[0045] k is the dielectric constant.
[0046] Wherein, E0, n, A and k can be approximately constant, then the change of the spacing between the plurality of interdigital electrodes 131 can be determined by the change of the capacitance value, so that the interdigital spacing anomaly can be found in time.
[0047] In some embodiments, the pad structure 15 and the contact structure 14 are integrally formed, which can make the connection between the pad structure 15 and the contact structure 14 more closely, reduce the joints and complex nodes, thereby improving the overall strength and stability, and the integrally formed design can simplify the manufacturing process, reduce the processing procedures and waiting time, and help to improve the production efficiency.
[0048] In some embodiments, the projected area of the pad structure 15 on the first substrate 11 is the same as the projected area of the connecting structure 132 on the first substrate 11, which can ensure that the contact between them is more closely and uniformly, thereby reducing the contact resistance. In other embodiments, the projected area of the pad structure 15 on the first substrate 11 is not the same as the projected area of the connecting structure 132 on the first substrate 11, which can adapt to different connection needs, for example, when the projected area of the pad structure 15 is slightly larger than the projected area of the connecting structure 132, it can be easier to realize the alignment and fixation during the welding process, thereby improving the connection efficiency and quality. For another example, when the projected area of the connecting structure 132 is larger, the heat dissipation area can be more effectively utilized, thereby improving the heat dissipation efficiency.
[0049] The semiconductor structure 1 includes multiple MEMS devices 13. Multiple pad structures 15 and multiple contact structures 14 are disposed on the conductive layer 12, with one pad structure 15 and one contact structure 14 corresponding to each other, and one MEMS device 13 corresponding to one pad structure 15. By assigning one pad structure 15 to each MEMS device 13, it is ensured that the interdigital spacing of each MEMS device 13 can be monitored through the contact structure 14. This allows for real-time monitoring of the interdigital spacing of multiple MEMS devices 13, facilitating the timely detection and repair of potential anomalies and improving the yield and reliability of the MEMS devices 13.
[0050] The conductive layer 12 includes an insulated first portion 121 and a second portion 122. The pad structure 15 includes a first pad structure 151 and a second pad structure 152. The contact structure 14 includes a first contact structure 141 and a second contact structure 142. The first pad structure 151 and the first contact structure 141 are spaced apart on the first portion 121, and the second pad structure 152 and the second contact structure 142 are spaced apart on the second portion 122. With this arrangement, the insulated first pad structure 151 and the second pad structure 152 allow the two ends of the multiple interdigital electrodes 131 to simulate the two poles of a capacitor. When a voltage is applied to the insulated first contact structure 141 and the second contact structure 142, it is equivalent to the first contact structure 141 and the second contact structure 142 providing power. Therefore, the spacing between the multiple interdigital electrodes 131 can be determined by measuring the capacitance value formed by the multiple interdigital electrodes 131.
[0051] In some embodiments, the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152 are identical in size and shape. This allows the use of the same molds, tools, and equipment during manufacturing, thereby simplifying the production process, reducing the number of mold and equipment changes, and improving production efficiency. Furthermore, the identical size and shape of the contact structure 14 and pad structure 15 make the testing process more standardized and automated, helping to ensure the accuracy and consistency of test results.
[0052] In some embodiments, the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152 are made of the same material. Using the same material allows for the use of the same manufacturing processes and equipment to prepare the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152, thereby optimizing the production process and improving production efficiency. In other embodiments, the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152 can also be made of different materials. By selecting different materials, the performance requirements of the contact structure 141 and the pad structure 152 in specific application scenarios can be met, thereby improving the contact effect and pad performance. The specific materials of the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152 can be set according to actual conditions and are not specifically limited here, as long as the first contact structure 141, the second contact structure 142, the first pad structure 151, and the second pad structure 152 can achieve conductivity.
[0053] In some embodiments, the pad structure 15, the contact structure 14, and the conductive layer 12 are made of the same material. The same conductive material can ensure that the electrical connection between the pad structure 15, the contact structure 14, and the conductive layer 12 is tighter and more reliable, reducing the risk of poor electrical contact or signal loss.
[0054] The first substrate 11 includes a carrier area for the MEMS device 13 and a non-carrier area surrounding the carrier area. The first pad structure 151 and the second pad structure 152 are located at the two ends of the carrier area, respectively. The connection structure 132 includes a first connection structure 1321 and a second connection structure 1322. The first connection structure 1321 is located on the side of the first pad structure 151 away from the first substrate 11, and the second connection structure 1322 is located on the side of the second pad structure 152 away from the first substrate 11. The first connection structure 1321 connects the first pad structure 151 and one end of the MEMS device 13, and the second connection structure 1322 connects the second pad structure 152 and the other end of the MEMS device 13, so that the MEMS device 13 is connected to the contact structure 14, thereby enabling the measurement of the spacing between multiple interdigitated fingers.
[0055] The first contact structure 141 and the second contact structure 142 are located in the non-load-bearing area. By placing the first contact structure 141 and the second contact structure 142 in the non-load-bearing area, it is convenient to realize the function of external power supply through the first contact structure 141 and the second contact structure 142 in subsequent packaging.
[0056] The conductive layer also includes a first dielectric layer 17, which is disposed in the middle region of the carrier area and connects the first portion 121 and the second portion 122. The first dielectric layer 17, the first connection structure 1321, the second connection structure 1322, the first pad structure 151, and the second pad structure 152 are connected to form a first cavity required for the operation of multiple interdigitated electrodes 131. By setting the first dielectric layer 133, the first portion 121 and the second portion 122 can be effectively electrically isolated. Furthermore, by connecting with the first connection structure 1321, the second connection structure 1322, the first pad structure 151, and the second pad structure 152 to form the first cavity, a higher degree of integration can be achieved within a limited space.
[0057] The conductor structure also includes a second substrate 16, which has a groove and is connected to the MEMS device 13 to enclose a second cavity required for the operation of multiple interdigitated electrodes 131.
[0058] The semiconductor structure 1 also includes a second dielectric layer 133, which is disposed on the side of the MEMS device 13 away from the first substrate 11, for bonding the MEMS device 13 and the second substrate 16.
[0059] The semiconductor structure 1 also includes a third dielectric layer 18, which is disposed between the first substrate 11 and the conductive layer 12.
[0060] In some embodiments, the material of the connecting structure 132 includes germanium.
[0061] In some embodiments, the first dielectric layer 17, the second dielectric layer 133, and the third dielectric layer 18 are made of the same material, namely silicon dioxide.
[0062] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.
Claims
1. A semiconductor structure for detecting the interdigital spacing, characterized in that, The semiconductor structure includes: First substrate; A conductive layer is disposed on one side of the first substrate, and the conductive layer is provided with a pad structure and a contact structure for electrical connection. The MEMS device is disposed on the side of the conductive layer away from the first substrate, and the MEMS device includes a plurality of interdigitated electrodes and a connection structure connected to the plurality of interdigitated electrodes. The connection structure is connected to the pad structure, and when a voltage is applied to the contact structure, the spacing between the multiple interdigitated electrodes in the MEMS device is determined by the capacitance value.
2. The semiconductor structure according to claim 1, characterized in that, The conductive layer includes an insulating first portion and a second portion. The pad structure includes a first pad structure and a second pad structure. The contact structure includes a first contact structure and a second contact structure. The first pad structure and the first contact structure are disposed on the first portion at intervals from each other. The second pad structure and the second contact structure are disposed on the second portion at intervals from each other.
3. The semiconductor structure according to claim 2, characterized in that, The first substrate includes a carrier region for the MEMS device and a non-carrier region surrounding the carrier region. The first pad structure and the second pad structure are located at the two ends of the carrier region, respectively. The connection structure includes a first connection structure and a second connection structure. The first connection structure is located on the side of the first pad structure away from the first substrate, and the second connection structure is located on the side of the second pad structure away from the first substrate.
4. The semiconductor structure according to claim 3, characterized in that, The conductive layer further includes a first dielectric layer, which is disposed in the middle region of the bearing area and connects the first part and the second part. The first dielectric layer, the first connection structure, the second connection structure, the first pad structure and the second pad structure are connected to form a first cavity required for the operation of the plurality of interdigitated electrodes.
5. The semiconductor structure according to claim 3, characterized in that, The first contact structure and the second contact structure are located in the non-load-bearing area.
6. The semiconductor structure according to any one of claims 1 to 5, characterized in that, The capacitance value is inversely proportional to the spacing between the plurality of interdigital electrodes.
7. The semiconductor structure according to any one of claims 1 to 5, characterized in that, The pad structure and the contact structure are integrally formed.
8. The semiconductor structure according to any one of claims 1 to 5, characterized in that, The conductive layer is provided with multiple pad structures and multiple contact structures, with one pad structure and one contact structure corresponding to each other; The semiconductor structure includes a plurality of MEMS devices, and one MEMS device is correspondingly configured with one pad structure.
9. The semiconductor structure according to any one of claims 1 to 5, characterized in that, The semiconductor structure also includes: The second substrate has a groove and is connected to the MEMS device to enclose a second cavity required for the operation of the plurality of interdigitated electrodes.
10. The semiconductor structure according to claim 9, characterized in that, The semiconductor structure further includes a second dielectric layer disposed on the side of the MEMS device away from the first substrate, for bonding the MEMS device and the second substrate.