TW201530147A - Active probe card - Google Patents

Abstract

An active probe card capable of improving testing bandwidth of a device under test includes a printed circuit board; at least one probe needle, affixed to a first plane of the printed circuit board, for probing the device under test; at least one connection member, electrically connected to the at least one probe needle; and an amplifier, formed on the printed circuit board and coupled to the at least one connection member, for amplifying an input or output signal of the device under test.

Description

Active probe device

The present invention relates to a probe device, and more particularly to an active probe device that can increase the test bandwidth.

In general, the finished wafer is tested to determine if the semiconductor component is functioning properly. In the wafer testing phase, the die on the wafer was electrically tested mainly by probe card, probe and tester. The probe card is a card with a number of fine probes that serves as a test interface for the tester and the semiconductor component to be tested. The needle measuring machine is responsible for accurately moving the wafers of the wafers to the correct position of the probe card, so that the probes on the probe card are in contact with the pads corresponding to the die. Then, the test machine sends a test signal through the probe card to test the function, parameters and characteristics of the semiconductor component.

Due to the rapid growth of wafer-level package, high-frequency circuits, and three-dimensional integrated circuits (3DIC) in recent years, the demand for wafer testing (Wafer probing or Chip probing, CP) for high-speed and RF testing has increased. . However, in the test of high-speed circuits, the characteristics of the probe are equivalent to parasitic inductance, and the high-speed test signal needs to pass through a relatively long signal path on the probe card before being transmitted to the semiconductor component to be tested, so when the high-speed test signal When reaching the semiconductor component to be tested, it has become quite weak.

On the other hand, as electronic products become more and more power-saving, the semiconductor components to be tested The driving ability is getting lower and lower. Therefore, the signal sent by the semiconductor component to be tested will have a lot of jitter noise after passing through the signal path and the probe on the probe card, which reduces the accuracy of the tester and reduces the testable bandwidth.

In view of this, how to improve the testable bandwidth of the semiconductor component to be tested to solve the test problem of the high-speed circuit is one of the important topics in the field.

One of the objects of the present invention is to provide an active probe device that utilizes active circuit components on a probe card to increase the testable bandwidth of a circuit under test to speed up the test process and improve the accuracy of the tester. Suitable for high speed and RF testing.

The invention discloses an active probe device which can improve the testable bandwidth of a circuit to be tested. The probe device includes a circuit board; at least one probe is fixed on a first side of the circuit board for detecting the circuit to be tested; at least one connector is electrically connected to the at least one probe; And an amplifying circuit formed on the circuit board and coupled to the at least one connecting component for amplifying an input signal or an output signal of the circuit to be tested.

10‧‧‧Test system

20, 30, 40, 50, 60, 70, 80, 90, 11‧‧‧ amplifying circuits

100, 200, 300, 400‧‧‧ active probe device

120‧‧‧Testing machine

140‧‧‧Needle measuring machine

12‧‧‧circuit to be tested

102, 202, 302, 402‧‧‧ circuit boards

104‧‧‧Fixed unit

106‧‧‧Probe

108, 108A, 108B‧‧‧ Connections

S1‧‧‧ first side

S2‧‧‧ second side

312A, 312B‧‧‧through holes

412‧‧‧ hole

INP, INPP, INPN, INP1P, INP1N‧‧‧ inputs

OUT, OUTP, OUTN, OUT1, OUT2, OUT1P, OUT1N, OUT2P, OUT2N‧‧‧ output

VIH, VIL, VCC, VCC‧‧‧ voltage

R1, R2, R3, R4‧‧‧ resistance

1 is a schematic diagram of a test system according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of an active probe device and a circuit to be tested according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of another active probe device and a circuit to be tested according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of another active probe device and a circuit to be tested according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

FIG. 6 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

Figure 7 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

FIG. 8 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

FIG. 9 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

FIG. 10 is a schematic diagram of an amplifying circuit according to an embodiment of the present invention.

Please refer to FIG. 1. FIG. 1 is a schematic diagram of a test system 10 according to an embodiment of the present invention. The test system 10 includes an active probe card 100, a tester 120, and a probe 140 to test the function of a circuit under test 12 (eg, a wafer). Parameters and characteristics. The active probe device 100 can increase the testable bandwidth of the circuit under test 12, and includes a circuit board 102, at least one fixing unit 104, at least one probe 106, and at least one connecting member 108. The circuit board 102 has two sides, the first side S1 faces the circuit under test 12, and the second side S2 faces the test machine 120. The connector 108 is electrically connected to the probe 106. The fixing unit 104 is configured to fix the probe 106 to the first surface S1 of the circuit board 102 and perform wafer testing (CP) on the circuit to be tested 12 (Wafer probing or Chip probing, CP). An amplifying circuit (not shown in FIG. 1) is formed on the circuit board 102, and is coupled to the connecting member 108 for amplifying an input signal or an output signal of the circuit 12 to be tested. In this way, the high-speed test signal is generated by the testing machine 120. Through the amplifying circuit on the active probe device 100, the test signal can be amplified by voltage or current to form an input signal with a large driving capability to input the circuit to be tested. 12 in. On the other hand, the output signal sent by the circuit under test 12 increases the current noise ratio of the signal after passing through the amplifying circuit on the active probe device 100, thereby reducing the interference of the noise on the test result. Therefore, the test system 10 can have a larger test bandwidth and better test accuracy, and increase the test speed.

In detail, the amplifying circuit is formed on the circuit board 102 of the active probe device 100 substantially at the closest position to the probe 106. The distance between one of the output terminals or an input of the amplifying circuit and the connected probe 106 should be substantially less than 10 cm for better amplification. please Referring to FIG. 2, FIG. 2 is a schematic diagram of an active probe device 200 and a circuit under test 12 according to an embodiment of the present invention. The active probe device 200 is used to implement the active probe device 100 of the test system 10, and the same components are denoted by the same reference numerals. In the active probe device 200, an amplifying circuit 20 is formed on the first side S1 of the circuit board 202, proximate to where the probe 106 is fixed. Since the amplifying circuit 20 and the probe 106 are both on the first surface S1 of the circuit board 202, the connecting member 108 can be directly electrically connected to the output end or the input end of the probe 106 and the amplifying circuit 20.

In some embodiments, the amplifying circuit and the probe can be disposed on different faces of the circuit board. Please refer to FIG. 3 , which is a schematic diagram of an active probe device 300 and a circuit 12 to be tested according to an embodiment of the present invention. The active probe device 300 is used to implement the active probe device 100 of the test system 10, and the same components are denoted by the same reference numerals. In the active probe device 300, an amplifying circuit 30 is formed on the second side S2 of the circuit board 302, approximately above the probe 106. The circuit board 302 has through holes (Via) 312A and 312B, and the connecting members 108A and 108B are electrically connected to the through holes 312A and 312B respectively at one end of the first surface S1 of the circuit board 302, and the amplifying circuit 30 is electrically connected to the through hole 312A. 312B is at the other end of the second side S2 of the circuit board 30. In another embodiment, a coaxial cable can be used in place of the via to achieve better high frequency electrical characteristics. Please refer to FIG. 4 , which is a schematic diagram of an active probe device 400 and a circuit 12 to be tested according to an embodiment of the present invention. The active probe device 400 is used to implement the active probe device 100 of the test system 10, and the same components are denoted by the same reference numerals. In the active probe device 400, an amplifying circuit 40 is formed on the second side S2 of the circuit board 402, approximately above the probe 106. The circuit board 402 has a hole 412. In this case, the connector 108 can be a coaxial cable that is disposed in the hole 412 and has one end connected to a probe 106 and the other end connected to the amplifying circuit 40.

It should be noted that the present invention forms an amplifying circuit on the circuit board of the probe card to amplify the voltage or current of the test signal, thereby increasing the testable bandwidth of the circuit to be tested. Those skilled in the art will be able to make various modifications, and are not limited thereto. For example, the application of the present invention does not Limited to the type of probe, the Cantilever probe, the Membrane probe, the spring probe, and the MEMS Probe Card probe card can be improved by the design of the present invention. Test the testable bandwidth of the circuit. Furthermore, the fixing unit is used for fixing the probe to the circuit board of the active probe device, and the material thereof may be ceramic material or electrically insulating plastic material, but other materials that do not affect the electrical characteristics of the probe may also be used. Implement a fixed unit.

The amplifying circuit of the present invention is for amplifying the voltage or current of the test signal, so that any circuit design having an amplifying voltage or current function can be suitably designed to be applied to the active probe device of the present invention. Please refer to FIG. 5. FIG. 5 is a schematic diagram of an amplifying circuit 50 according to an embodiment of the present invention. The amplifying circuit 50 is applicable to the foregoing embodiment (such as the amplifying circuit 20, 30, 40), which is a driving chip, and includes an input terminal INP and an output terminal OUT. The amplifying circuit 50 can be used to amplify the input signal of the circuit under test 12 and/or the output signal of the circuit 12 to be tested. More specifically, when the input signal of the circuit under test 12 needs to be amplified, the input terminal INP of the amplifying circuit 50 disposed on the active probe device 100 (or 200, 300, 400) can be coupled to the testing machine 120. The output end OUT of the amplifying circuit 50 of the active probe device 100 is coupled to a connecting member 108, and the voltage or current of the test signal is amplified and increased by a probe 106. The driving capability of the input signal of the circuit under test 12. On the other hand, when the output signal of the circuit 12 to be tested needs to be amplified, the output terminal OUT of the amplifier circuit 50 disposed on the active probe device 100 can be coupled to a test signal input terminal of the test machine 120. The input terminal INP of the amplifying circuit 50 of the active probe device 100 is coupled to the other connector 108, and the other connector 108 detects the output signal sent by the circuit under test 12 via the other probe 106. After the output signal sent by the measuring circuit 12 is amplified by voltage or current, the current noise ratio of the signal is increased, and the interference of the noise on the test result is reduced. One or more sets of amplifying circuits 50 may also be disposed on the active probe device 100 to determine the manner in which the connecting member 108 and the testing machine 120 are coupled according to the measurement requirements.

Please refer to FIG. 6. FIG. 6 is a schematic diagram of an amplifying circuit 60 according to an embodiment of the present invention. The amplifying circuit 60 is applicable to the foregoing embodiments (such as the amplifying circuits 20, 30, 40), and includes a single-ended operational amplifier for amplifying the voltage or current of the input signal or the output signal of the circuit 12 to be tested, and as a buffer. Buffer. Similar to the amplifying circuit 50 shown in FIG. 5, the amplifying circuit 60 includes an input terminal INP and an output terminal OUT. When the input signal of the circuit under test 12 needs to be amplified, the input terminal INP of the amplifying circuit 60 disposed on the active probe device 100 (or 200, 300, 400) can be coupled to a test signal output of the testing machine 120. The output terminal OUT of the amplifier circuit 60 of the active probe device 100 is coupled to a connector 108, and the voltage or current of the test signal is amplified by a probe 106, thereby increasing the circuit 12 to be tested. Input signal drive capability. On the other hand, when the output signal of the circuit 12 to be tested needs to be amplified, the output terminal OUT of the amplifier circuit 60 disposed on the active probe device 100 can be coupled to a test signal input terminal of the test machine 120. The input terminal INP of the amplifying circuit 60 of the active probe device 100 is coupled to the other connector 108. The other connector 108 detects the output signal sent by the circuit under test 12 via the other probe 106. After the output signal sent by the measuring circuit 12 is amplified by voltage or current, the current noise ratio of the signal is increased, and the interference of the noise on the test result is reduced. One or more sets of amplifying circuits 60 may be disposed on the active probe device 100 to determine the manner in which the connecting member 108 and the testing machine 120 are coupled according to the measurement requirements.

The active probe device 100 (or 200, 300, 400) may also include an amplifying circuit having a differential input and an output for measuring the differential signal. Please refer to FIG. 7. FIG. 7 is a schematic diagram of an amplifying circuit 70 according to an embodiment of the present invention. The amplifying circuit 70 is applicable to the foregoing embodiments (such as the amplifying circuits 20, 30, 40), and includes a differential operational amplifier, which can be used when the input signal or the output signal of the circuit under test 12 is a differential signal. The amplifier circuit 70 includes input terminals INPP, INPN, and output terminals OUTP, OUTN. When the input signal of the circuit under test 12 needs to be amplified, the input terminals INPP and INPN of the amplifying circuit 70 provided in the active probe device 100 (or 200, 300, 400) can be respectively coupled to the difference of the testing machine 120. The test signal output terminal is coupled to the output terminals OUTP and OUTN of the amplifying circuit 70 of the active probe device 100 respectively coupled to the differential signal transmitting The two connecting members 108 are respectively connected to the two probes 106, and the amplified differential test signals are fed into the circuit under test 12. On the other hand, when the output signal of the circuit 12 to be tested needs to be amplified, the output terminals OUTP and OUTN of the amplifier circuit 70 disposed on the active probe device 100 can be respectively coupled to the differential test signal input of the test machine 120. The input terminals INPP and INPN of the amplifying circuit 70 of the active probe device 100 are respectively coupled to the other two connecting members 108 for transmitting the differential signals, and then respectively detected by the two probes 106 to be tested. The differential output signal sent by the circuit 12 increases the current noise ratio of the output signal. Similarly to the related description of the amplifying circuit 50, one or more sets of amplifying circuits 70 may be disposed on the active probe device 100 to determine the manner in which the connecting member 108 and the testing machine 120 are coupled according to the measurement requirements.

Please refer to FIG. 8 to FIG. 10, which are schematic diagrams of the amplifying circuits 80, 90, and 11 respectively according to an embodiment of the present invention. The amplifying circuit 80 is applicable to the foregoing embodiments (such as the amplifying circuits 20, 30, 40) and includes a single-ended comparator including an input terminal INP and output terminals OUT1, OUT2. The amplifying circuit 90 is applicable to the foregoing embodiments (such as the amplifying circuits 20, 30, 40) and includes a differential comparator including an input terminal INP and output terminals OUT1P, OUT1N, OUT2P, OUT2N. The amplifying circuit 11 is applicable to the foregoing embodiment (such as the amplifying circuit 20, 30, 40), and includes an equalizer including an input terminal INP1P, INP1N and output terminals OUT1P, OUT1N, wherein the equalizer has Stylized or fixed a pre-emphasis and/or a solution enhancement. Since the test signal passes through the signal path and the probe on the probe card, the attenuation of the low frequency part and the high frequency part of the signal is usually inconsistent. Generally, the high frequency part has a large degree of attenuation, and therefore, the available The amplifying circuit 11 of the equalizer amplifies the high frequency portion of the signal by a large magnification (ie, the high frequency signal passes through the pre-emphasis function of the equalizer), and amplifies the low frequency portion of the signal by a small magnification (low frequency signal) Through the solution enhancement function of the equalizer, the signal size after amplification of the high frequency and low frequency signals is substantially equalized. Among them, the equalizer magnification can be designed as a programmable or fixed value to meet the needs of practical applications. The connection manners of the input terminals and the output terminals of the amplifying circuits 80, 90, 11 are similar to those described above for the amplifying circuits 50, 60, 70, and those skilled in the art should refer to the above. The description is inferred, so the details will not be described again.

In addition, the amplifying circuits 50, 60, 70, 80, 90, and 11 can be used in combination according to different measurement requirements. For example, the amplifying circuit 50 amplifies the input signal of the circuit 12 to be tested, and the amplifying circuit 60 amplifies the input signal. The output signal of the circuit 12 to be tested is, but not limited to, the output signal.

In summary, the present invention utilizes an amplifying circuit in the vicinity of the probe to form an active probe device. The amplifying circuit can include a driving chip, a differential operational amplifier, a single-ended operational amplifier, and a difference. a comparator, a single-ended comparator or an equalizer to increase the input signal and/or the output signal driving capability of the circuit under test. Therefore, the active probe device of the present invention can reduce the noise to the test result. Interference, and improve test bandwidth, test accuracy and test speed, suitable for high-speed circuit testing.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

20‧‧‧Amplification circuit

200‧‧‧Active probe device

12‧‧‧circuit to be tested

102‧‧‧ boards

104‧‧‧Fixed unit

106‧‧‧Probe

108‧‧‧Connecting parts

S1‧‧‧ first side

S2‧‧‧ second side

Claims (9)

An active probe device for improving the testable bandwidth of a circuit to be tested, the active probe device comprising: a circuit board; at least one probe fixed to one of the first sides of the circuit board for Detecting the circuit to be tested; at least one connecting member electrically connected to the at least one probe; and an amplifying circuit formed on the circuit board and coupled to the at least one connecting member for amplifying the waiting One of the measurement circuits inputs a signal or an output signal. The active probe device of claim 1, wherein the amplifying circuit is a driving wafer. The active probe device of claim 1, wherein the amplifying circuit comprises: a differential operational amplifier or a single-ended operational amplifier; or a differential comparator or a single-ended comparator; or an equalizer . The active probe device of claim 3, wherein the equalizer has a pre-emphasis function and/or a de-emphasis function, the pre-enhancement function is for providing a first magnification, and the de-emphasis function is used for A second magnification is provided, the first magnification is greater than the second magnification, and the first magnification and the second magnification are programmable or fixed values. The active probe device of claim 1, wherein the amplifying circuit is formed on the circuit board opposite to a second side of the first face. The active probe device of claim 5, wherein the circuit board has at least a uniform hole, and the at least one connecting member is electrically connected to the at least one of the first holes of the circuit board. The amplifying circuit is electrically connected to the at least one hole at the second side of the circuit board. The active probe device of claim 5, wherein the circuit board has a hole, the at least one connecting member is a coaxial cable, and the hole is inserted through the hole, one end is connected to the at least one probe, and the other end is connected to The amplifying circuit. The active probe device of claim 1, wherein a distance between an output or an input of the amplifying circuit and the at least one probe is substantially less than 10 cm. The active probe device of claim 1, further comprising at least one fixing unit for fixing the at least one probe to the first side of the circuit board, wherein one of the at least one fixing unit is Ceramic material or electrical insulating plastic material.