Test system and test method thereof

Abstract

The invention provides a test system and a test method thereof, the test system is used for trimming a fuse, and the test system comprises a probe card and a test machine. The probe card includes a first probe and a second probe electrically connected to both ends of the fuse. The probe card further comprises a driving circuit. The drive circuit electrically connects the number of test channels to the first probe and electrically connects the ground terminal to the second probe based on the control signal to generate a trimming current to trim the fuse. The test machine executes a test program to read a state signal and provide a test channel and a ground terminal, and generates a control signal based on the state signal. When the test machine judges that the fuse is not finished successfully, the test machine adjusts the state signal to increase the finishing current.

Description

TECHNICAL FIELD

[0001] The present application relates to a test system for trimming a fuse and a test method thereof, and more particularly to a test system for trimming a fuse and a test method thereof, which can adaptively adjust a trimming current for trimming the fuse. BACKGROUND

[0002] After the manufacture of an integrated circuit, the integrated circuit often needs to be calibrated for voltage and / or current through chip probing test before subsequent packaging. Generally, the chip probing test is usually achieved by trimming a fuse to adjust the voltage and / or current.

[0003] However, in the process of trimming the fuse, the fuse often cannot be successfully blown due to insufficient trimming current, and the tester can only increase the trimming current and perform batch testing again by checking the yield after testing a predetermined number of dies. Similarly, a predetermined number of dies need to be completed to determine whether the increased trimming current is sufficient to blow all fuses.

[0004] Since the trimming current for trimming the fuse needs to be adjusted each time, batch testing is required before determining whether to continue to increase the trimming current based on the yield of the batch testing, which prolongs the test time of the chip probing test and consumes a large amount of manpower and cost. Therefore, it is necessary to optimize the trimming current adjustment method to increase the test efficiency. SUMMARY

[0005] Therefore, the present application proposes a test system for trimming a fuse. The test system includes a probe card and a test machine. The probe card includes a first probe and a second probe electrically connected to two ends of the fuse, and further includes a driving circuit. The driving circuit electrically connects a channel number of test channels to the first probe and a ground terminal to the second probe based on a control signal to generate a trimming current for trimming the fuse. The test machine executes a test program to read a state signal and provide the test channels and the ground terminal, and generates the control signal based on the state signal. When the test machine determines that the fuse is not successfully trimmed, the test machine adjusts the state signal to increase the trimming current.

[0006] The present application further provides a testing method for trimming a fuse. The testing method includes reading a status signal, setting a trimming current based on the status signal, electrically connecting a first probe and a second probe to both ends of the fuse and trimming the fuse using the trimming current, determining whether the fuse is successfully trimmed, and increasing the trimming current and trimming the fuse again when the fuse is not successfully trimmed. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 is a block diagram of a testing system according to an embodiment of the present application;

[0008] Figure 2 is a flowchart of a testing method according to an embodiment of the present application.

[0009] [SYMBOL DESCRIPTION]

[0010] 10: fuse

[0011] 100: testing system

[0012] 110: probe card

[0013] 111: driving circuit

[0014] 112: memory unit

[0015] 120: testing machine

[0016] 200: testing method

[0017] PRB1: first probe

[0018] PRB2: second probe

[0019] CH1: first testing channel

[0020] CH2: second testing channel

[0021] CH3: third testing channel

[0022] CHN: Nth testing channel

[0023] GND: ground

[0024] ST: status signal

[0025] SCTL: control signal

[0026] ITRM: trimming current

[0027] M: testing state

[0028] N: number of channels

[0029] C: channel current

[0030] S210~S290: Steps and procedures. Detailed Implementation

[0031] The following description is an embodiment of the present invention. Its purpose is to illustrate the general principles of the invention and should not be considered as a limitation thereof. The scope of the invention should be defined by the claims.

[0032] It is worth noting that the following disclosure provides multiple embodiments or examples for practicing different features of the invention. The specific examples and arrangements of elements described below are only for briefly illustrating the spirit of the invention and are not intended to limit the scope of the invention. Furthermore, the same element symbols or words may be repeated in multiple examples in the following description. However, the purpose of repetition is only to provide a simplified and clear description and is not intended to limit the relationship between the various embodiments and / or configurations discussed below.

[0033] Furthermore, the descriptions in the following specification of a feature being connected to, coupled to, and / or formed on another feature may actually include multiple different embodiments, including features that are in direct contact, or additional features that are formed between features, such that the features are not in direct contact.

[0034] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms, and these terms are only used to distinguish different elements, components, regions, layers, and / or portions. Therefore, a first element, component, region, layer, and / or portion discussed below may be referred to as a second element, component, region, layer, and / or portion without departing from the teachings of some embodiments of the present invention.

[0035] Some embodiments of the present invention can be understood in conjunction with the accompanying drawings, which are also considered part of the description of the embodiments of the present invention. It should be understood that the drawings of the embodiments of the present invention are not drawn to scale with actual devices and components. The shape and thickness of the embodiments may be exaggerated in the drawings to clearly show the features of the embodiments of the present invention. Furthermore, the structures and devices in the drawings are illustrated schematically to clearly show the features of the embodiments of the present invention.

[0036] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the relevant art and the background or context of the invention, and should not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of the invention.

[0037] In some embodiments of the present invention, terms such as "connection" and "interconnection," unless specifically defined, may refer to two structures in direct contact, or to two structures not in direct contact, wherein another structure is disposed between the two structures. Furthermore, these terms regarding joining and connection may also include cases where both structures are movable or both structures are fixed.

[0038] In a diagram, similar elements and / or features may have the same element symbol. Elements of the same type can be distinguished by adding letters or numbers after the element symbol to differentiate similar elements and / or features.

[0039] Figure 1 This is a block diagram of a test system according to an embodiment of the present invention. Figure 1 As shown, the test system 100 includes a probe card 110 and a test platform 120. The probe card 110 includes a first probe PRB1 and a second probe PRB2, wherein the first probe PRB1 and the second probe PRB2 are electrically connected to the two ends of the fuse 10. According to some embodiments of the present invention, the probe card 110 may include any number of probes, and the probe card 110 may also be electrically connected to the two ends of any number of fuses simultaneously. Here, only the first probe PRB1 and the second probe PRB2 being electrically connected to the two ends of the fuse 10 is described and explained, and is not limited in any way.

[0040] Test equipment 120 provides a first test channel CH1, a second test channel CH2, a third test channel CH3... and an Nth test channel CHN, as well as a ground terminal GND, and executes a test program. When test equipment 120 executes the test program, it moves probe card 110 to electrically connect the first probe PRB1 and the second probe PRB2 to the two ends of fuse 10, and executes the test method to read the status signal ST and generate a control signal SCTL based on the status signal ST. Therefore, based on the control signal SCTL, probe card 110 electrically connects the N test channels to the first probe PRB1 and connects the ground terminal GND to the second probe PRB2.

[0041] like Figure 1As shown, the probe card 110 further includes a drive circuit 111 and a memory unit 112. The drive circuit 111, based on the control signal SCTL generated by the test equipment 120, electrically connects N test channels (first test channel CH1, second test channel CH2, third test channel CH3... and Nth test channel CHN) to the first probe PRB1, and electrically connects the ground terminal GND to the second probe PRB2. The memory unit 112 is used to store the status signal ST. According to some embodiments of the present invention, the test channels generate a trimming current ITRM, which blows the fuse 10 by flowing through the trimming current ITRM.

[0042] According to some embodiments of the present invention, the status signal ST includes test status M, number of channels N, and channel current C. When the test equipment 120 determines that fuse 10 adjustment has failed, the test equipment 120 sets test status M to a failure state. According to some embodiments of the present invention, whenever the test equipment 120 determines that fuse 10 adjustment has failed, the test equipment 120 will repeatedly set test status M to a failure state. In other words, once test status M is set to a failure state, test status M remains in a failure state unless the tester resets test status M.

[0043] The drive circuit 111 electrically connects the test channels of the number N channels to the first probe PRB1 based on the number N channels of the status signal ST. According to some embodiments of the invention, the drive circuit 111 may include multiple relays ( Figure 1 (Not shown), by switching relays, it is selected whether to electrically connect any of the first test channel CH1, the second test channel CH2, the third test channel CH3... and the Nth test channel CHN to the first probe PRB1. According to some embodiments of the present invention, the first test channel CH1, the second test channel CH2, the third test channel CH3... and the Nth test channel CHN have a maximum output current limitation, while the ground terminal GND does not have a maximum output current limitation.

[0044] The test equipment 120 sets the maximum output current of the N test channels electrically connected to the first probe PRB1 based on the channel current C. Therefore, the trimming current ITRM output by the first probe PRB1 is the sum of the maximum output currents of the N test channels. According to some embodiments of the invention, the channel current C is used to set the maximum output current of each of the N test channels, meaning that each of the N test channels has the same maximum output current. According to other embodiments of the invention, the channel current C can also set the maximum output current of any one of the N test channels, meaning that each of the N test channels has a different maximum output current.

[0045] Figure 2 This is a flowchart of a test method according to an embodiment of the present invention. The following is for... Figure 2 The description of test method 200 will be combined with Figure 1 The test system 100 is described in detail below.

[0046] When the test equipment 120 starts executing the test program, the test equipment 120 reads the status signal ST stored in the memory unit 112 (step S210) and determines whether the test status M of the status signal ST is a failure status (step S220). When it is determined that the above test status M is not a failure status, the test equipment 120 sets the number of channels N to a preset number and sets the channel current C to a preset current (step S230).

[0047] Next, the test equipment 120 generates a trimming current ITRM based on the test state M and the channel current C (step S240). According to some embodiments of the present invention, when the number of channels N is a preset number and the channel current C is a preset current, the trimming current ITRM is a preset current. Returning to step S220, when it is determined that the above-mentioned test state M is a failure state, the test equipment 120 executes step S240, generating a trimming current ITRM based on the number of channels N and the channel current C of the memory unit 112, wherein the trimming current ITRM is greater than the preset current.

[0048] According to some embodiments of the present invention, at the beginning of each test program execution, the test machine 120 sets the test state M to a non-failure state, and in step S230, the test machine 120 sets the number of channels N to a preset number and the channel current C to a preset current based on the non-failure test state M, and then stores the preset number and the preset current in the memory unit 112.

[0049] In other words, at the start of each test program execution, the test equipment 120 resets the test state M to a non-failure state and sets the number of channels N and the channel current C of the memory unit 112 to preset values ​​and stores them in the memory unit 112. Furthermore, regardless of whether the test state M is a failure state, the test equipment 120 generates a trimming current ITRM based on the number of channels N and the channel current C of the memory unit 112.

[0050] like Figure 2As shown, step S240 further includes steps S241 and S242. In step S241, the test equipment 120 uses the control signal SCTL to control the drive circuit 111 to electrically connect the M test channels to the first probe PRB1 and to electrically connect the ground terminal GND to the second probe PRB2. Then, in step S242, the test equipment 120 sets the maximum output current of the M test channels based on the channel current C.

[0051] Subsequently, the testing equipment 120 moves the probe card 110, electrically connecting the first probe PRB1 and the second probe PRB2 to both ends of the fuse 10, and uses the trimming current ITRM to trim the fuse 10 (step S250). Then, the testing equipment 120 determines whether the fuse 10 has been successfully trimmed (step S260). According to one embodiment of the present invention, when the testing equipment 120 determines that there is a short circuit between the first probe PRB1 and the second probe PRB2, it means that the fuse 10 has not melted, that is, the trimming of the fuse 10 has not been successful. According to another embodiment of the present invention, when the testing equipment 120 determines that there is an open circuit between the first probe PRB1 and the second probe PRB2, it means that the fuse 10 has melted, that is, the trimming of the fuse 10 has been successful.

[0052] When the test equipment 120 determines in step S260 that the fuse 10 adjustment is unsuccessful, the test equipment 120 sets the test state M to a failed state (step S270) and increases the number of channels N and / or the channel current C (step S280). Next, the test equipment 120 executes step S240 again, generating an adjustment current ITRM based on the increased number of channels N and the channel current C, and using the increased adjustment current ITRM to adjust the fuse 10 again.

[0053] According to one embodiment of the present invention, the test equipment 120 sets the test state M to a failure state each time it determines that the fuse 10 has failed to be repaired. In other words, after the test equipment 120 sets the test state M to a failure state for the first time, the test state M will remain in the failure state until the test equipment 120 re-executes the test program, at which point the test state M will be reset to a non-failure state.

[0054] Returning to step S260, when the testing equipment 120 determines that fuse 10 has been successfully repaired, the testing equipment 120 determines whether there is a next fuse (step S290). If it is determined in step S290 that there is a next fuse, the testing equipment 120 executes steps S210 to S280 to repair the next fuse. If it is determined in step S290 that there is no next fuse, the testing equipment 120 ends the test program and terminates test method 200.

[0055] To further illustrate the invention in detail, the following will use a preset quantity of 1 and a preset current of 100mA as an example, combined with...Figure 1 Test system 100 and Figure 2 The test method 200 is provided for illustrative purposes. However, the present invention is not limited thereto in any way.

[0056] When the test equipment 120 starts executing the test program and performs test method 200, it first resets the test state M, and then, based on the fact that the test state M is not in a failure state, sets the number of channels N and the channel current C to a preset number and a preset current, respectively (step S230). That is, it sets the number of channels N to 1 and the channel current C to 100mA.

[0057] Next, in steps S240 to S250, the test instrument 120 controls the drive circuit 111 to electrically connect the first test channel CH1 to the first probe PRB1 and to the ground terminal GND to the second probe PRB2. When the first test channel CH1 supplies power to the first probe PRB1, the maximum value of the trimming current ITRM flowing through the fuse 10 is 100mA (i.e., the channel current C).

[0058] When the testing equipment 120 determines that the fuse 10 adjustment is unsuccessful, the testing equipment 120 increases the number of channels N and / or the channel current C. According to one embodiment of the present invention, the testing equipment 120 can increase the number of channels N from 1 to 2, so that the drive circuit 111 electrically connects both the first test channel CH1 and the second test channel CH2 to the first probe PRB1. According to another embodiment of the present invention, the testing equipment 120 can increase the channel current C from 100mA to 200mA. Therefore, whether the number of channels N is doubled or the channel current C is doubled, the adjustment current ITRM will be doubled.

[0059] According to some embodiments of the present invention, the channel current C can be set such that the maximum output current of all test channels electrically connected to the first probe PRB1 is the same, or the maximum output current of each test channel electrically connected to the first probe PRB1 can be set separately. For example, the drive circuit 111 electrically connects the first test channel CH1, the second test channel CH2, and the third test channel CH3 to the first probe PRB1. According to one embodiment of the present invention, the maximum output current of the first test channel CH1, the second test channel CH2, and the third test channel CH3 is 100mA based on the channel current C. According to another embodiment of the present invention, the maximum output current of the first test channel CH1, the second test channel CH2, and the third test channel CH3 is 100mA, 200mA, and 300mA respectively based on the channel current C.

[0060] In other words, the channel current C can be set to have the same maximum output current for all test channels, or individual test channels can be set to have different maximum output currents. Furthermore, the trimming current ITRM is the sum of the maximum output currents of all test channels electrically connected to the first probe PRB1. Therefore, the test equipment 120 can arbitrarily increase the number of channels N and / or the channel current C to increase the trimming current ITRM.

[0061] According to one embodiment of the present invention, when the test equipment 120 successfully repairs fuse 10 using the trimming current ITRM, the test equipment 120 continues to repair the next fuse using the same trimming current ITRM. According to one embodiment of the present invention, when the test equipment 120 fails to repair fuse 10 using the trimming current ITRM, the test equipment 120 can arbitrarily increase the number of channels N and / or the channel current C to increase the trimming current ITRM and repair fuse 10 again.

[0062] This invention presents a test system and method for fuse trimming. Whenever fuse trimming fails, the proposed test system and method immediately increase the number of channels and / or the channel current to increase the trimming current, and then use the increased trimming current to trim the fuse again until trimming is successful. In other words, the test system and method of this invention can increase the trimming current after fuse trimming failure and immediately trim the fuse again, adaptively selecting the most suitable trimming current for each batch. Compared to traditional test methods that require completing a batch of tests before adjusting the trimming current, the proposed test system and method help improve the efficiency and yield of fuse trimming during testing, and significantly reduce the required testing personnel time and testing costs.

[0063] While the embodiments and advantages of the present invention have been disclosed above, it should be understood that any person skilled in the art can make modifications, substitutions and refinements without departing from the spirit and scope of the present invention.

Claims

1. A test system, characterized by, A method for trimming a fuse, comprising: providing a probe card including a first probe and a second probe electrically connected to two ends of the fuse, wherein the probe card further includes: a driving circuit electrically connecting a number of test channels to the first probe and a ground terminal to the second probe based on a control signal to generate a trimming current to trim the fuse; and a test machine executing a test procedure to read a status signal and provide the test channels and the ground terminal, and generating the control signal based on the status signal; wherein when the test machine determines that the fuse is not successfully trimmed, the test machine adjusts the status signal to increase the trimming current.

2. The test system of claim 1, wherein, The probe card further includes a memory unit for storing the status signal; wherein the status signal includes a test status, the number of test channels, and a channel current; wherein when the fuse trimming fails, the test machine sets the test status as a failure status; wherein the test machine sets a maximum output current of each of the number of test channels based on the channel current; wherein when the test status is the failure status, the test machine adjusts the number of test channels and / or the channel current to increase the trimming current.

3. The test system of claim 2, wherein, The test procedure includes the following steps: reading the status signal of the memory unit; determining whether the test status is the failure status; when the test status is not the failure status, setting the number of test channels and the channel current as a preset number and a preset current, respectively; generating the trimming current based on the preset number and the preset current; and electrically connecting the first probe and the second probe to the two ends of the fuse, and trimming the fuse with the trimming current.

4. The test system of claim 3, wherein, The test procedure further includes the following steps: when the test status is the failure status, generating the trimming current based on the number of test channels and the channel current stored in the memory unit; wherein the trimming current is a sum of maximum output currents of the number of test channels.

5. The test system of claim 3, wherein, The test procedure further includes the following steps: after the step of electrically connecting the first probe and the second probe to the two ends of the fuse, and trimming the fuse with the trimming current, determining whether the fuse is successfully trimmed; when it is determined that the fuse is not successfully trimmed, increasing the number of test channels and / or the channel current to increase the trimming current, and storing the increased number of test channels and / or the channel current in the memory unit; based on the increased number of test channels and the channel current, executing again the step of electrically connecting the first probe and the second probe to the two ends of the fuse, and trimming the fuse with the trimming current; and when it is determined that the fuse is successfully trimmed, trimming another fuse based on the number of test channels and / or the channel current of the memory unit.

6. A testing method for trimming a fuse, characterized by, The test method includes: reading a status signal; based on the status signal, setting a trimming current; electrically connecting a first probe and a second probe to both ends of the fuse, and trimming the fuse with the trimming current; determining whether the fuse is successfully trimmed; and when the fuse is not successfully trimmed, increasing the trimming current and trimming the fuse again.

7. The test method of claim 6, wherein, the status signal includes a test status, a channel number, and a channel current; wherein the test method further includes: when the fuse is not successfully trimmed, setting the test status as a failure status; wherein when the test status is the failure status, the test status remains the failure status.

8. The test method of claim 7, wherein, the step of setting the trimming current based on the status signal further includes: determining whether the test status is the failure status; when the test status is the failure status, generating the trimming current based on the channel number and the channel current; when the test status is not the failure status, setting the channel number and the channel current as a preset number and a preset current, respectively; and generating the trimming current based on the preset number and the preset current.

9. The test method of claim 8, wherein, the step of generating the trimming current based on the channel number and the channel current further includes: electrically connecting a test channel of the channel number to the first probe and electrically connecting a ground end to the second probe; and setting a maximum output current of each of the test channel of the channel number based on the channel current; wherein the trimming current is a sum of output currents of the test channel of the channel number.

10. The test method of claim 7, wherein, the step of increasing the trimming current and trimming the fuse again further includes: increasing the channel number and / or the channel current to increase the trimming current; and trimming the fuse again with the increased trimming current; wherein the test method further includes: when the fuse is successfully trimmed, trimming a next fuse with the increased trimming current.

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