TWI479157B - Probe card structure - Google Patents

Description

Probe card structure

The present invention relates to a probe card, and more particularly to a probe card structure.

According to the method for detecting whether the electrical connection between the precision electronic components of the electronic product is true, a probe card is used as a transmission interface between the test signal and the power signal between the detecting machine and the electronic object to be tested. The electronic component to be tested generally receives the high frequency power signal from the detector to supply the power required for the electronic component to be tested.

However, the transmission line of the power signal of the conventional probe card is usually designed with the same impedance as the transmission line of the test signal. In other words, when the detector transmits a high-frequency power signal to the probe card, the power supply of the probe card The high impedance generated by the line at high frequencies usually causes a certain degree of attenuation of the power signal. In this way, the electronic component to be tested is likely to stop operating due to insufficient power supply or to generate a misjudgment of the test signal.

In view of the above, the main object of the present invention is to provide a probe card structure capable of avoiding a large attenuation of a power signal when transmitting a high frequency power signal.

In order to achieve the above object, the probe card structure provided by the present invention is used for transmitting a power signal and a test signal of a detecting machine to an electronic object to be tested. The power signal is supplied to the electronic object to be tested, and the electronic object to be tested is electrically detected through the test signal; the probe card structure comprises a plurality of signal pins, a substrate and at least one power coaxial cable; Wherein, the signal pins are made of a conductive material, and one end thereof is used to touch the electronic object to be tested; the substrate is made of a dielectric material having a specific dielectric constant for connection with the detector, and embedded therein a first signal conductor formed by a conductor; the first signal conductor is electrically connected to the detector and the other end of the at least one signal pin for transmitting the test signal to the corresponding signal pin to The power electronic cable includes: a signal line located at a central location, a dielectric layer covering the signal line, and a ground line outside the dielectric layer; the signal line and the detector and the The other end of the at least one signal pin is electrically connected to transmit the power signal to the electronic object to be tested through the corresponding signal pin; the dielectric layer is used to isolate the signal line and A ground line; the ground line is used as a ground.

In addition, for the above purpose, the power coaxial cable meets the following conditions: 1/5 ≦ Φ _P1 / Φ _P2 <1; wherein Φ _P1 is the wire diameter of the signal line; Φ _P2 is the path length of the dielectric layer.

Therefore, through the above design, the power coaxial cable can have the characteristics of low impedance value, thereby avoiding a large attenuation when the probe card structure transmits the high frequency power signal.

In order to more clearly illustrate the invention, the preferred embodiment Detailed description is as follows.

Referring to FIG. 1 , the probe card structure of the preferred embodiment of the present invention is used to transmit the power signal and the test signal outputted by the power terminal 110 and the signal terminal 120 of the detector 100 to an electronic object 200 to be tested. The power signal supplies power to the electronic object 200 to be tested, and electrically detects the electronic object 200 to be tested through the test signal. The probe card structure includes a plurality of signal pins 10, a substrate 20, a carrier 30, and a power coaxial cable 40. among them:

The signal pins 10 are made of metal. Of course, other conductive materials may be used. One end of the signal pins 10 is used to touch the to-be-tested part or the power supply part of the electronic object 200 to be tested.

One side of the substrate 20 is for connection to the detector 100. In this embodiment, the substrate 20 is a multilayer printed circuit board, and is formed with a first signal conductor 21 made of a conductor, a first power conductor 22, and a plurality of surrounding first signal conductors 21. The first ground conductor 23 of the first power conductor 22 is embedded therein. The first signal conductor 21 is connected to the signal terminal 120.

The carrier 30 is connected to the other side of the substrate 20. In this embodiment, the carrier 30 is a multi-layer ceramic (MLC), and is formed with a second signal conductor 31, a second power conductor 32, and a plurality of conductors. A second ground conductor 33 surrounding the second signal conductor 31 and the second power conductor 32 is embedded therein. The second signal conductor 31 One end is connected to the first signal conductor 21, and the other end is connected to the signal pin 10 for touching the to-be-measured portion of the electronic object 200 to be tested. The second power conductor 32 has one end connected to the first power conductor 22 and the other end connected to the signal pin 100 for touching the to-be-powered portion of the electronic object 200 to be tested.

The power coaxial cable 40 includes a signal line 41 at a center position, a dielectric layer 42 covering the signal line 41, and a ground line 43 outside the dielectric layer 42. The signal line 41 is connected to the power terminal 110 of the detector 100 and the first power conductor 22 of the substrate 20 for transmitting the power signal. The dielectric layer 42 is used to isolate the signal line 41 from the ground line 43 to avoid a short circuit. The grounding wire 43 is used as a ground.

Therefore, the first signal conductor 21 of the substrate 20 and the second signal conductor 31 of the carrier 30 are connected in series to form a signal line for conducting the test signal outputted by the signal terminal 120 of the detector 100, and The probe 10 is transmitted to the to-be-tested portion of the electronic object 200 to be tested. The signal line 41 of the power coaxial cable 40, the first power conductor 22 of the substrate 20, and the second power conductor 32 of the carrier 30 are connected in series to form a power line for conducting the detector 100. The power signal outputted by the power terminal 110 is transmitted to the to-be-powered portion of the electronic object 200 to be tested through the corresponding probe 10.

As a result, the first power conductor 22 and the second power conductor 32 directly penetrating the substrate 20 and the carrier 30 do not generate an electric field reaction sufficient to affect the impedance value of the substrate 20 and the carrier 30. Therefore, the impedance value of the above power supply line is mainly controlled and adjusted by the impedance design of the power coaxial cable 40. Thereby, the power coaxial cable 40 can be designed according to the following conditions: 1. 1/5 ≦ Φ _P1 / Φ _P2 <1; 2. Φ _P1 / ΦP ₂ ≧ HS ₁ / T _S1 ; 3. Φ _P1 / _{Φ P2 ≧ H S2 / T S2} ;. 4 R P ≦ R S1;. 5 R P ≦ R S2; 6 E P ≧ E S1;. 7 E P ≧ E S2;. with Figures 2 to 4, Wherein Φ _{P1 is} the wire diameter of the signal line 41; Φ _{P2 is} the diameter of the dielectric layer 42; R _{P is} the resistivity of the signal line 41; R _{S1 is} the resistivity of the first signal conductor 21; _{P is} the dielectric constant of the dielectric layer 42; E _{S is} the dielectric constant of the substrate 20; H _S1 is the thickness of the first signal conductor 21; T _{S1 is} the substrate 20 around the first signal conductor 21, The thickness of the dielectric material between the two adjacent first ground conductors 23; H _{S2 is} the thickness of the second signal conductor 31; T _{S2 is} the carrier 30 around the second signal conductor 31, The thickness of the dielectric material between the two adjacent second ground conductors 33. In this way, the power coaxial cable 40 is designed to have a low resistance value that is much lower than the signal line, and the high dielectric constant, and the signal line 41 and the dielectric layer 42 are transmitted through the low resistivity. The ratio of the diameter design makes the power coaxial cable 40 have a higher capacitance value, so that it has a very low reactance value at a high frequency, so that the power coaxial cable 40 transmits a high frequency signal. When the high frequency power signal outputted by the detector 100 is transmitted to the electronic object 200 to be tested, the power signal can be prevented from being greatly attenuated.

Of course, in actual implementation, according to the gap between the parts to be tested of the electronic object to be tested 200, it is possible to design only use the substrate 20, or directly use only the power coaxial cable for transmission of the power signal, and achieve the purpose of the present invention. . In addition, the power source conductor of the substrate 20 or the carrier 30 can be directly disposed on the surface of the substrate 20 or the carrier 30, or other designs, in addition to the above-mentioned design for direct penetration, so that the electric field reaction does not affect the whole. The impedance value is used to avoid the influence of the power conductor of the substrate 20 or the carrier 30 on the transmission of the power signal. Furthermore, the above description is only a preferred embodiment of the present invention, and equivalent structural changes in the scope of the present invention and the scope of the claims are intended to be included in the scope of the present invention.

10‧‧‧Signal needle

20‧‧‧Substrate

21‧‧‧First Signal Conductor

22‧‧‧First power conductor

23‧‧‧First grounding conductor

30‧‧‧ Carrier Board

31‧‧‧Second signal conductor

32‧‧‧Second power conductor

33‧‧‧Second grounding conductor

40‧‧‧Power coaxial cable

41‧‧‧Signal line

42‧‧‧ dielectric layer

43‧‧‧ Grounding wire

100‧‧‧Detector

110‧‧‧Power terminal

120‧‧‧ Signal Terminal

200‧‧‧Electronic objects to be tested

1 is a cross-sectional view of a power coaxial cable; FIG. 3 is a cross-sectional view taken along line A-A of FIG. 1; and FIG. 4 is a cross-sectional view taken along line B-B of FIG.

10‧‧‧Signal needle

20‧‧‧Substrate

21‧‧‧First Signal Conductor

22‧‧‧First power conductor

23‧‧‧First grounding conductor

30‧‧‧ Carrier Board

31‧‧‧Second signal conductor

32‧‧‧Second power conductor

33‧‧‧Second grounding conductor

40‧‧‧Power coaxial cable

100‧‧‧Detector

110‧‧‧Power terminal

120‧‧‧ Signal Terminal

200‧‧‧Electronic objects to be tested

Claims (8)

A probe card structure for transmitting a power signal and a test signal of a detector to an electronic object to be tested, thereby supplying power to the electronic object to be tested through the power signal, and transmitting the electronic signal to be tested through the test signal The probe card structure comprises: a plurality of signal pins, which are made of a conductive material, and one end of which is used to touch the electronic object to be tested; and a substrate is made of a dielectric material having a specific dielectric constant. The first signal conductor is electrically connected to the detector, and the other end of the at least one signal pin is electrically connected to the detector. Transmitting the test signal to the electronic object to be tested through the corresponding signal pin; the at least one power coaxial cable includes a signal line at a central position, a dielectric layer covering the signal line, and located at the a grounding wire outside the dielectric layer; the signal line is electrically connected to the detecting machine and the other end of the at least one signal pin for transmitting the power signal through the corresponding signal pin The electronic object to be tested; the dielectric layer for isolating the signal line and the ground line; is used as the ground line grounded; a coaxial cable of the power supply meets the following _{conditions: 1/5 ≦ Φ P1 /} Φ P2 <1 Where Φ _P1 is the wire diameter of the signal line; Φ _P2 is the path length of the dielectric layer. The probe card structure of claim 1, wherein the power coaxial cable is more in conformity with the following condition: R _P ≦R _S1 ; wherein R _P is a resistivity of the signal line; and R _{S1 is} the first signal conducting The resistivity of the body. The probe card structure of claim 1, wherein the power coaxial cable is more in conformity with the following condition: E _P ≧ E _S1 ; wherein E _P is a dielectric constant of the dielectric layer; E _{S1 is} a dielectric constant of the substrate . The probe card structure of claim 1, wherein the substrate further comprises a plurality of first ground conductors configured to be grounded and disposed around the first signal conductor; the power coaxial cable is more suitable for the following conditions : Φ _P1 /Φ _P2 ≧H _S1 /T _S1 ; wherein H _S1 is the thickness of the first signal conductor; T _{S1 is} the substrate is adjacent to the first signal conductor, and the two first grounds adjacent thereto The thickness of the dielectric material between the conductors. The probe card structure of claim 1, further comprising a carrier connected to the substrate, and having a second signal conductor made of a conductor and a plurality of seconds disposed around the second signal conductor a grounding conductor; the second signal conductor is connected to the first signal conductor and the corresponding signal pin; and the second ground conductor is used as a ground. The probe card structure of claim 5, wherein the power coaxial cable is more in conformity with the following condition: R _P ≦ R _S2 ; wherein R _P is a resistivity of the signal line; and R _{S2 is} the second signal conducting The resistivity of the body. The probe card structure of claim 5, wherein the power coaxial cable is more in conformity with the following condition: E _P ≧ E _S2 ; wherein E _P is a dielectric constant of the dielectric layer; E _S2 is a medium of the carrier constant. The probe card structure of claim 5, wherein the power coaxial cable is more in accordance with the following condition: Φ _P1 /Φ _P2 ≧H _S2 /T _S2 ; wherein H _S2 is the thickness of the second signal conductor; T _{S2 is} the thickness of the dielectric material between the carrier and the second ground conductor adjacent to the second signal conductor.