Wafer detection probe card
By dividing into independent contact one and contact two in the connection part of the probe card, and connecting it through the Kelvin connection method, the measurement error problem of existing probe cards during high-precision small resistance measurement is solved, and higher testing accuracy is achieved.
Patent Information
- Application Number
- CN202421634672.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-11
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2034-07-11
AI Technical Summary
When performing high-precision small resistance measurement, the contacts in the connection are continuous, resulting in the cable voltage difference being included in the internal voltage drop of the system, resulting in measurement errors.
A wafer detection probe card is designed, and the contacts in the connection part are divided into independent contact one and contact two, and are electrically connected to the soldering pin plate through the Kelvin connection method to eliminate the voltage drop on the conductor.
Through independent contact connection, the voltage drop is eliminated during the test and the test accuracy is improved.
Smart Images
Figure CN222965296U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor testing technology, and particularly to a wafer detection probe card. Background Art
[0002] In the industry, a probe card is often used to test wafers. The function of the probe card is to realize signal transmission between the test instrument and the wafer, that is: one end of the probe contacts the contact point on the probe card, and the other end contacts the metal pad on the chip to be tested, and cooperate with the test instrument and related software to complete. The main method for the semiconductor industry to measure wafers through a probe card is the two-terminal measurement method.
[0003] Such as Figure 1 , the contact points in the connection part on the existing probe card are connected together and the two-terminal measurement method is used for testing. However, the voltage difference of the cable connecting the measurement unit is included in the internal voltage drop of the system, resulting in measurement errors, which will cause the measurement results to be untrue and have certain limitations in measuring small resistances with high precision. Utility Model Content
[0004] This application provides a wafer detection probe card to solve the problem of measurement errors in the above-mentioned existing technology, and adopts the following technical solutions:
[0005] The wafer detection probe card includes a substrate and probes. The surface of the substrate includes an inner circle area and an outer circle area. A ring-shaped welding needle plate is provided in the middle of the inner circle area. One end of the probe is connected to the welding needle plate, and the other end is used to contact the wafer for detecting the wafer. A plurality of connection parts are provided in the outer circle area. The connection part includes independently provided contact point one and contact point two. The contact point one and the contact point two are electrically connected to the welding needle plate through the Kelvin connection method.
[0006] Preferably, a plurality of connection parts are also provided in the inner circle area. The connection parts in the inner circle area include independently provided contact point one and contact point two.
[0007] Preferably, the contact point one and the contact point two are connected to the welding needle plate through a coaxial line inside the substrate, and both ends of the coaxial line are grounded.
[0008] Preferably, it further includes a grounding area, and the grounding area includes a first grounding area provided around the connection part and a second grounding area provided outside the periphery of the welding needle plate.
[0009] Preferably, the connection parts are circumferentially distributed in the inner circle area and the outer circle area along the axis of the substrate.
[0010] Preferably, the coaxial line includes a first wire and a second wire. The first wire connects the contact point one to the welding needle plate, and the second wire connects the contact point two and the welding needle plate.
[0011] The beneficial effects of this application compared with the prior art are as follows:
[0012] The contacts in the connection part are divided into independent contact one and contact two, so that the test can be carried out by the Kelvin test method, and it can ensure that the voltage drop on the wire is eliminated during the test, thereby improving the test accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 is a schematic diagram of the structure of the existing probe card;
[0014] Figure 2 is a schematic diagram of the structure of the probe card of this application;
[0015] Figure 3 is a schematic diagram of a partial structure of the probe card of this application;
[0016] Figure 4 is a connection schematic diagram of the probe card of this application;
[0017] In the figure:
[0018] 1. Substrate, 5. Second grounding area, 6. Probe pad, 8. Probe, 9. Coaxial cable;
[0019] 10. Connection part, 30. Inner circular area, 40. Outer circular area, 50. First grounding area, 110. Contact one, 120. Contact two. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the drawings of this application. Obviously, the described embodiments of this application are only partial embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.
[0021] Combined with Figures 2 to 4 , this application is further described. The wafer detection probe card includes a substrate 1 and probes 8. The surface of the substrate 1 includes an inner circular area 30 and an outer circular area 40. A ring of probe pads 6 is provided in the middle of the inner circular area 30. One end of the probe 8 is connected to the probe pad 6, and the other end is used to contact the wafer for wafer detection. A plurality of connection parts 10 are provided in the outer circular area 40. The connection parts 10 are connected to the probe pads 6 through coaxial cables 9 inside the substrate. The connection parts 10 include independently provided contact one 110 and contact two 120. The contact one 110 and the contact two 120 are electrically connected to the probe pad 6 by the Kelvin connection method.
[0022] The contacts of the probe card in the prior art are connected together and tested by the two-terminal measurement method. During the test, the voltage difference on the wire is included in the internal voltage drop of the system, resulting in measurement errors and inaccurate testing. The improvement compared with the prior art is that the contact one 110 and the contact two 120 in the connecting portion 10 are divided into two independent contacts, and the probe 8 is respectively connected through the coaxial line 9 inside the substrate 1. This structure can realize the Kelvin test method. The contact one 110 is the Force terminal (force line), and the contact two 120 is the Sense terminal (sense line), which are respectively externally connected to the test bench, and can ensure that the voltage drop on the wire is eliminated during the test, thereby improving the test accuracy.
[0023] Combined with Figure 2 , several connecting portions 10 can also be provided in the inner circular area 30. The connecting portions in the inner circular area have the same structure as those in the outer circular area; the connecting portion in the inner circular area 30 includes an independently provided contact one and a contact two; the connecting portion in the inner circular area 30 is located between the solder pin pad 6 and the outer circular area 40; among them, the connecting portion 10 is circumferentially distributed along the axis of the substrate 1 in the inner circular area 30 and the outer circular area 40, and the number of the connecting portions 10 is not limited.
[0024] Combined with Figure 4 , the coaxial line 9 in this application includes a wire one and a wire two. The contact one 110 is connected to the solder pin pad 6 through the wire one, and the contact two 120 is connected to the solder pin pad 6 through the wire two to connect the probe 8. Both ends of the coaxial line 9 are grounded; specifically, the grounding area includes a first grounding area 50 and a second grounding area 5. The first grounding area 50 is provided outside the connecting portion 10, and the second grounding area 5 is provided outside the solder pin pad. The first grounding area 50 and the second grounding area 5 are both connected to the grounding connection point on the test bench to prevent leakage of the probe card.
Claims
1. A wafer detection probe card, comprising a substrate and a probe, wherein the substrate surface comprises an inner circle area and an outer circle area, wherein a ring-shaped soldering needle disk is provided in the middle of the inner circle area, wherein one end of the probe is connected to the soldering needle disk, and the other end is used to contact the wafer to detect the wafer, and wherein the probe is characterized in that: The outer circular area is provided with a plurality of connection parts, and the connection parts include a contact point 1 and a contact point 2 which are independently arranged, and the contact point 1 and the contact point 2 are electrically connected to the soldering pin plate through a Kelvin connection method.
2. The wafer inspection probe card according to claim 1, characterized in that: The inner circle area is also provided with a plurality of connection parts, and the connection parts of the inner circle area include the contact point 1 and the contact point 2 which are independently provided.
3. The wafer inspection probe card according to claim 1 or 2, characterized in that: The first contact and the second contact are connected to the soldering pin plate via a coaxial line in the substrate, and both ends of the coaxial line are grounded.
4. The wafer inspection probe card according to claim 1, characterized in that: The device also includes a grounding area, wherein the grounding area includes a first grounding area arranged around the connecting portion and a second grounding area arranged at the periphery of the soldering pin pad.
5. The wafer inspection probe card according to claim 1, characterized in that: The connection portions are distributed circumferentially in the inner circular area and the outer circular area along the axis of the substrate.
6. The wafer inspection probe card according to claim 3, characterized in that: The coaxial line includes a first conductor and a second conductor. The first conductor connects the first contact point to the soldering pin plate, and the second conductor connects the second contact point to the soldering pin plate.