Antifuse detection method, fusing method, chip

Abstract

The present disclosure relates to the technical field of semiconductor, and provides a method for detecting anti-fuse, a method for fusing, and a chip. The method for detecting anti-fuse comprises: obtaining measured resistances of a to-be-detected anti-fuse at multiple different temperatures; judging a correlation between the measured resistance and the temperature of the to-be-detected anti-fuse; judging whether the to-be-detected anti-fuse is completely fused according to the correlation between the measured resistance and the temperature of the to-be-detected anti-fuse; and when the measured resistance and the temperature of the to-be-detected anti-fuse are positively correlated, judging that the to-be-detected anti-fuse is completely fused. The method for detecting anti-fuse can accurately judge whether the to-be-detected anti-fuse is completely fused.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and in particular to an antifuse detection method, a fusing method, and a chip. Background Technology

[0002] In related technologies, the inspection method for antifuse wires typically includes: detecting the measured resistance of the antifuse wire, and determining whether the antifuse wire is completely blown by judging the relationship between the measured resistance and the threshold resistance. Specifically, when the measured resistance is less than the threshold resistance, it can be determined that the antifuse wire is completely blown.

[0003] However, the antifuse may be in a state of edge-blown failure. In this state, the measured resistance of the antifuse is less than the threshold resistance, and under certain environmental conditions, the antifuse may return to a non-blown state. Therefore, the inspection methods in related technologies cannot detect antifuses in an edge-blown state.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] According to one aspect of this disclosure, an antifuse detection method is provided, the detection method comprising:

[0006] Obtain the measured resistance of the antifuse under test at multiple different temperatures;

[0007] Determine the correlation between the measured resistance and temperature of the antifuse under test;

[0008] Determine whether the anti-fuse under test is completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test;

[0009] Specifically, when the measured resistance of the anti-fuse under test is positively correlated with the temperature, it is determined that the anti-fuse under test is completely melted.

[0010] In an exemplary embodiment of this disclosure, determining whether the anti-fuse under test is completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test further includes:

[0011] When the measured resistance of the antifuse under test is negatively correlated with the temperature, it is determined that the antifuse under test is not completely melted.

[0012] In an exemplary embodiment of this disclosure, determining whether the anti-fuse under test is completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test further includes:

[0013] When the measured resistance of the antifuse under test is neither positively nor negatively correlated with the temperature, the measured resistance of the antifuse under test at multiple different temperatures is obtained again, and the correlation between the measured resistance and the temperature of the antifuse under test is re-determined.

[0014] In one exemplary embodiment of this disclosure, obtaining the measured resistance of the antifuse under test at multiple different temperatures includes:

[0015] The measured resistance of the antifuse under test at the first temperature is taken as the first resistance;

[0016] The measured resistance of the antifuse wire under test at a second temperature is obtained as the second resistance, wherein the first temperature is greater than the second temperature;

[0017] Determining the correlation between the measured resistance and temperature of the antifuse under test includes:

[0018] Compare the values ​​of the first resistor and the second resistor;

[0019] When the first resistance is greater than the second resistance, it is determined that the measured resistance of the antifuse under test is positively correlated with the temperature.

[0020] In one exemplary embodiment of this disclosure, the first temperature is greater than or equal to 80 degrees Celsius, and the second temperature is less than or equal to 40 degrees Celsius.

[0021] In one exemplary embodiment of this disclosure, the detection method further includes:

[0022] Compare the measured resistance of the antifuse under test with the preset resistance at different temperatures;

[0023] When the measured resistance of the antifuse under test is greater than the preset resistance, it is determined that the antifuse under test is not completely melted.

[0024] When the measured resistance of the anti-fuse under test is less than the preset resistance, the test anti-fuse under test is then judged to be completely melted based on the correlation between the measured resistance of the anti-fuse under test and the temperature.

[0025] In one exemplary embodiment of this disclosure, the detection method further includes:

[0026] Obtain the mapping relationship between resistance and temperature when the anti-fuse is fully fused;

[0027] The theoretical resistance corresponding to the measured resistance of the antifuse to be tested is obtained according to the mapping relationship, wherein the corresponding measured resistance and theoretical resistance correspond to the same temperature;

[0028] A first parameter is obtained based on a plurality of measured resistances and a plurality of theoretical resistances. The first parameter characterizes the difference between the theoretical resistance and the measured resistance. The larger the first parameter is, the greater the difference between the theoretical resistance and the measured resistance.

[0029] When the first parameter is greater than the first threshold, it is determined that the anti-fuse wire under test is not completely melted;

[0030] When the first parameter is less than the first threshold, the correlation between the measured resistance and temperature of the anti-fuse under test is used to determine whether the anti-fuse under test is completely melted.

[0031] In one exemplary embodiment of this disclosure, obtaining the mapping relationship between the resistance and temperature of a fully fused anti-fuse includes:

[0032] Provide a fully fused anti-fuse wire;

[0033] Obtain the measured resistance of the fully fused antifuse at different temperatures;

[0034] Establish a functional model of the measured resistance and temperature of the fully fused anti-fuse, wherein the functional model includes at least one undetermined constant;

[0035] The undetermined constant is obtained based on the measured resistance and temperature of at least one set of the fully fused antifuse wires.

[0036] In one exemplary embodiment of this disclosure, the function model is:

[0037] Y = aX + b, where the temperature is the independent variable, the measured resistance is the dependent variable, and a and b are the undetermined constants.

[0038] In one exemplary embodiment of this disclosure, the plurality of measured resistors form a first vector, and the plurality of theoretical resistors form a second vector;

[0039] The first parameter is any one of the following distances between the first vector and the second vector: Minkowski distance, Euclidean distance, Manhattan distance, and Canberra distance.

[0040] In one exemplary embodiment of this disclosure, the minimum temperature difference between the different temperatures is greater than or equal to 10 degrees Celsius.

[0041] In one exemplary embodiment of this disclosure, the detection method further includes: heating the antifuse wire to be tested to different temperatures;

[0042] Heating the antifuse wire to be tested to different temperatures includes:

[0043] The antifuse to be tested is placed in an environment with a preset temperature to heat the antifuse to the preset temperature.

[0044] In one exemplary embodiment of this disclosure, the detection method further includes: heating the antifuse wire to be tested to different temperatures;

[0045] Heating the antifuse wire to be tested to different temperatures includes:

[0046] The anti-fuse to be tested is placed in a current path, and the anti-fuse to be tested is heated to different temperatures by the current.

[0047] In one exemplary embodiment of this disclosure, obtaining the measured resistance of the antifuse under test at multiple different temperatures includes:

[0048] The antifuse to be tested and a known resistor are connected in series between the first power supply terminal and the second power supply terminal, wherein the voltage at the first power supply terminal is greater than the voltage at the second power supply terminal.

[0049] The measured resistance of the antifuse under test is obtained based on the voltage at the node between the antifuse under test and the known resistor.

[0050] According to one aspect of this disclosure, a method for blowing an anti-fuse is provided, the method comprising:

[0051] The anti-fuse wire under test is blown off.

[0052] The antifuse to be tested is subjected to a detection action, the detection action including the antifuse detection method described above;

[0053] If the detection action cannot determine that the anti-fuse under test is completely blown, the blow-off action and detection action are repeated for the anti-fuse under test.

[0054] According to one aspect of this disclosure, a chip is provided, the chip including an antifuse, the antifuse in the chip being melted by the antifuse melting method described above.

[0055] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0056] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0057] Figure 1 The curves showing the relationship between voltage and current of the antifuse under different conditions;

[0058] Figure 2 A flowchart illustrating an exemplary embodiment of the antifuse detection method of this disclosure;

[0059] Figure 3 This is a graph showing the relationship between the resistance and temperature of the antifuse when it is fully melted.

[0060] Figure 4 This is a graph showing the relationship between the resistance and temperature of an antifuse in a partially melted state.

[0061] Figure 5 This is a schematic diagram of the structure for obtaining the measured resistance of the antifuse under test in an exemplary embodiment of the antifuse detection method of this disclosure;

[0062] Figure 6 This is a schematic diagram of the structure for obtaining the measured resistance of the antifuse in another exemplary embodiment of the antifuse detection method of this disclosure;

[0063] Figure 7 This is a logic diagram of an exemplary embodiment of the anti-fuse blowing method disclosed herein;

[0064] Figure 8 This is a logic diagram of another exemplary embodiment of the anti-fuse blowing method of this disclosure. Detailed Implementation

[0065] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that this disclosure will be more comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0066] The terms “a,” “one,” and “the” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended meaning of inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.

[0067] In related technologies, an antifuse is a common one-time programmable device widely used in the design of various chips. An antifuse typically consists of two terminals with a dielectric layer between them. When a breakdown voltage is applied to the two terminals of the antifuse, the dielectric layer between the terminals breaks down, causing the antifuse to melt and thus drastically reducing the resistance between the terminals. Utilizing this characteristic of antifuses, specific logic signals can be stored by melting the antifuse.

[0068] In related technologies, the extent to which an antifuse has blown is typically determined by the measured resistance of the antifuse. For example, if the measured resistance is less than the threshold resistance, the antifuse is considered completely blown; otherwise, it is considered not to have blown.

[0069] However, the antifuse may not completely melt after the activation action; it may remain in a partially melted state. Even in this partially melted state, the measured resistance of the antifuse is still less than the threshold resistance. However, after a period of operation or after processes such as infrared reflow soldering, the antifuse in this partially melted state may return to a non-melted state. Therefore, the inspection methods in related technologies cannot detect antifuses in a partially melted state. For example, as... Figure 1 The figure shows the relationship between voltage and current of the antifuse under different conditions. The horizontal axis represents the voltage applied to the two terminals of the antifuse, and the vertical axis represents the current of the antifuse. Figure 1 Curve 11 shows the relationship between the voltage and current at the two terminals of the antifuse when it is in the edge-fused state; curve 12 shows the relationship between the voltage and current at the two terminals of the antifuse after being baked at 98 degrees Celsius for 1 hour; and curve 13 shows the relationship between the voltage and current at the two terminals of the antifuse after being baked at 98 degrees Celsius for 12 hours. According to... Figure 1 It can be seen that the resistance of the anti-fuse increases after being subjected to high temperature for 1 hour, meaning that the anti-fuse will return to the non-fuse state from the edge-broken state under high temperature.

[0070] Based on this, this exemplary embodiment provides an antifuse detection method, such as... Figure 2 The diagram shown is a flowchart of an exemplary embodiment of the antifuse detection method of this disclosure. The detection method may include:

[0071] Step S1: Obtain the measured resistance of the antifuse under test at multiple different temperatures;

[0072] Step S2: Determine the correlation between the measured resistance and temperature of the antifuse to be tested;

[0073] Step S3: Determine whether the antifuse under test is completely melted based on the correlation between the measured resistance and temperature of the antifuse under test;

[0074] Specifically, when the measured resistance of the anti-fuse under test is positively correlated with the temperature, it is determined that the anti-fuse under test is completely melted.

[0075] In this exemplary embodiment, as Figure 3 , 4 As shown, Figure 3 This is a graph showing the relationship between the resistance and temperature of the antifuse when it is fully fused. Figure 4This is a graph showing the relationship between the resistance and temperature of the antifuse in an incompletely melted state. Among them, Figure 3 The relationship between resistance and temperature for five samples in a fully fused state is shown. Figure 4 The relationship between resistance and temperature for five samples under incomplete melting conditions is shown. Based on... Figure 3 It can be seen that when the antifuse is fully melted, it exhibits the temperature characteristics of a conductor material; the resistance of the antifuse is positively correlated with temperature, meaning that the resistance increases with increasing temperature. According to... Figure 4 It can be seen that when the antifuse is in a partially melted state, it exhibits the temperature characteristics of an insulator or semiconductor material. The resistance of the antifuse is negatively correlated with temperature, meaning that the resistance decreases as the temperature increases. It should be noted that in this exemplary embodiment, the partially melted state can include an edge-melted state and a non-melted state.

[0076] In this exemplary embodiment, the antifuse detection method determines whether the antifuse under test is completely melted based on the correlation between the measured resistance and temperature of the antifuse under test. Specifically, when the measured resistance and temperature of the antifuse under test are positively correlated, the antifuse under test is determined to be completely melted. This detection method can accurately detect completely melted antifuses and can exclude antifuses in a state of partial melting.

[0077] In this exemplary embodiment, determining whether the antifuse under test is completely melted based on the correlation between the measured resistance and temperature of the antifuse under test may further include:

[0078] When the measured resistance of the antifuse under test is negatively correlated with temperature, it is determined that the antifuse under test is not completely melted. That is, the antifuse under test may be in a state of partial melting or non-melting.

[0079] This detection method can accurately determine whether the anti-fuse wire under test is in a state of incomplete melting.

[0080] In this exemplary embodiment, when measuring the resistance and temperature of the antifuse under test, errors or mistakes may occur, resulting in the measured resistance and temperature of the antifuse under test not being positively or negatively correlated.

[0081] In this exemplary embodiment, determining whether the antifuse under test is completely melted based on the correlation between the measured resistance and temperature of the antifuse under test may further include:

[0082] When the measured resistance of the antifuse under test is neither positively nor negatively correlated with the temperature, the measured resistance of the antifuse under test at multiple different temperatures is obtained again, and the correlation between the measured resistance and the temperature of the antifuse under test is re-determined.

[0083] This testing method can eliminate abnormal correlations caused by errors in the resistance or temperature of the antifuse under test by retesting.

[0084] It should be understood that, in other exemplary embodiments, to simplify the detection steps, when the measured resistance of the antifuse under test is neither positively nor negatively correlated with temperature, the detection method can also directly determine whether the antifuse is completely melted by the ratio of the number of abnormal measured resistances to the total number of measured resistances. For example, the detection method can detect the measured resistance of the antifuse under test at M different temperatures. Among the M measured resistances, there are K abnormal measured resistances and MK normal measured resistances. The MK normal measured resistances are positively or negatively correlated with temperature, and the multiple measured resistances formed by the MK normal measured resistances and any one abnormal measured resistance are neither positively nor negatively correlated with temperature. When the number of abnormal measured resistances accounts for a small proportion of the total number of measured resistances, it can be considered that the abnormal measured resistances are due to measurement errors or mistakes, and thus the complete melt of the antifuse under test can be determined based on the correlation between the normal measured resistances and temperature. For example, when K / M is less than or equal to 20%, the correlation between the measured resistance and temperature can be used to determine whether the antifuse under test is completely blown. Specifically, when the measured resistance and temperature are positively correlated, the antifuse under test is considered completely blown; when they are negatively correlated, the antifuse under test is considered incompletely blown. K / M can be equal to 20%, 15%, 10%, 5%, 1%, etc. K and M are positive integers.

[0085] It should be understood that, in other exemplary embodiments, determining whether the antifuse under test is completely melted based on the correlation between the measured resistance and temperature of the antifuse under test may also include:

[0086] When the measured resistance and temperature of the antifuse under test are not positively correlated, it is directly determined that the antifuse is not completely blown. The non-positive correlation between measured resistance and temperature can include any situation other than a positive correlation; for example, a negative correlation, or neither a positive nor a negative correlation. This detection method can also simplify the detection steps.

[0087] In this exemplary embodiment, when detecting the measured resistance of the antifuse, the minimum temperature difference between different temperatures can be greater than or equal to 10 degrees Celsius. For example, the minimum temperature difference between different temperatures can be equal to 10 degrees Celsius, 20 degrees Celsius, 30 degrees Celsius, 40 degrees Celsius, 50 degrees Celsius, 60 degrees Celsius, etc. In this exemplary embodiment, the sufficiently large temperature difference between different temperatures allows for a sufficiently large resistance difference between the theoretical resistances of the antifuse under test at different temperatures. Therefore, even if there is a small error in the measured resistance, this measurement error will not cause the correlation between the measured resistance and temperature to change.

[0088] In this exemplary embodiment, obtaining the measured resistance of the antifuse under test at multiple different temperatures may include:

[0089] The antifuse to be tested is placed in an environment at a preset temperature to heat the antifuse to be tested to the preset temperature;

[0090] The resistance of the antifuse under test at the preset temperature is the measured resistance corresponding to the preset temperature.

[0091] In this exemplary embodiment, the antifuse to be tested is placed in the heating cavity of a heating device, and the temperature of the heating cavity is adjusted by the heating device to heat the antifuse to be tested. This method can effectively control the temperature of the antifuse to be tested.

[0092] However, antifuse is usually integrated into the chip, and other components in the chip may be damaged by high temperatures.

[0093] In other exemplary embodiments, the detection method may also heat the antifuse under test in other ways. For example, obtaining the measured resistance of the antifuse under test at multiple different temperatures may include:

[0094] The antifuse under test is placed in a current path to heat it. This heating method avoids exposing the entire chip containing the antifuse to a high-temperature environment, thereby reducing the risk of chip damage from high temperatures.

[0095] In this exemplary embodiment, as Figure 5 The diagram shown is a schematic representation of an exemplary embodiment of the antifuse detection method of this disclosure, illustrating the process of obtaining the measured resistance of the antifuse under test. Obtaining the measured resistance of the antifuse under test at multiple different temperatures may include:

[0096] The antifuse ATF to be tested and a known resistor R are connected in series between a first power supply terminal VDD and a second power supply terminal VSS, where the voltage at the first power supply terminal VDD is greater than the voltage at the second power supply terminal VSS. The measured resistance of the antifuse ATF is obtained based on the voltage at node N between the antifuse ATF and the known resistor R. The measured resistance of the antifuse ATF is equal to R(V1-VSS) / (VDD-V1), where R is the resistance of the known resistor, V1 is the voltage at node N, VSS is the voltage at the second power supply terminal, and VDD is the voltage at the first power supply terminal.

[0097] It should be understood that, in other exemplary embodiments, this detection method can also determine the detection method for the antifuse resistance based on the connection method of the antifuse to be tested in the chip. For example, as... Figure 6 The diagram shown illustrates the structure for obtaining the measured resistance of an antifuse in another exemplary embodiment of the antifuse detection method of this disclosure. In this exemplary embodiment, the antifuse can be applied to a dynamic random access memory (DRAM) to repair faulty memory cells. The row address signal Xadd can select the first switch unit T1, and the column address signal Yadd can select the second switch unit T2, thereby connecting the antifuse ATF to be tested at a specific location and the third switch unit T3 in series between the high-level power supply terminal Vdd and the low-level power supply terminal Vss. In this exemplary embodiment, the on-resistance of the first switch unit T1 and the second switch unit T2 can be ignored. The third switch unit T3 has a known on-resistance, and the detection method can also obtain the resistance of the antifuse ATF to be tested by detecting the voltage at node N.

[0098] In this exemplary embodiment, before determining whether the anti-fuse under test has completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test, the detection method may further include:

[0099] Compare the measured resistance of the antifuse under test with the preset resistance at different temperatures;

[0100] When the measured resistance of the antifuse under test is greater than the preset resistance, it is determined that the antifuse under test is not completely melted.

[0101] When the measured resistance of the anti-fuse under test is less than the preset resistance, the test anti-fuse under test is then judged to be completely melted based on the correlation between the measured resistance of the anti-fuse under test and the temperature.

[0102] In this exemplary embodiment, the detection method can first compare the measured resistance of the antifuse under test with the preset resistance at different temperatures to exclude antifuses that are not in a fused state, thereby improving the accuracy of antifuse detection.

[0103] In this exemplary embodiment, before determining whether the anti-fuse under test has completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test, the detection method may further include:

[0104] Obtain the mapping relationship between resistance and temperature when the anti-fuse is fully fused;

[0105] The theoretical resistance corresponding to the measured resistance of the antifuse to be tested is obtained according to the mapping relationship, wherein the corresponding measured resistance and theoretical resistance correspond to the same temperature;

[0106] A first parameter is obtained based on a plurality of measured resistances and a plurality of theoretical resistances. The first parameter characterizes the difference between the theoretical resistance and the measured resistance. The larger the first parameter is, the greater the difference between the theoretical resistance and the measured resistance.

[0107] When the first parameter is greater than the first threshold, it is determined that the anti-fuse wire under test is not completely melted;

[0108] When the first parameter is less than the first threshold, the correlation between the measured resistance and temperature of the anti-fuse under test is used to determine whether the anti-fuse under test is completely melted.

[0109] In this exemplary embodiment, the detection method obtains the theoretical resistance of the antifuse under test by mapping the resistance of the completely melted antifuse to temperature, and preliminarily determines whether the antifuse is completely melted by the difference between the theoretical resistance and the measured resistance. When the difference between the theoretical resistance and the measured resistance of the antifuse is large, it can be determined that the antifuse is not completely melted; when the difference between the theoretical resistance and the measured resistance of the antifuse is small, it can be further determined whether the antifuse is completely melted based on the correlation between the measured resistance and temperature. This detection method can also further improve the accuracy of the detection.

[0110] It should be noted that the method of "comparing the first parameter and the first threshold" and the method of "comparing the measured resistance and the preset resistance" can be applied to the same embodiment or to different embodiments.

[0111] In this exemplary embodiment, the mapping relationship between the resistance and temperature of the fully fused antifuse is obtained as y = f(x), where x is the temperature at which the antifuse is fully fused and y is the resistance of the fully fused antifuse. Obtaining the theoretical resistance corresponding to the measured resistance of the antifuse under test based on this mapping relationship may include: substituting the temperature corresponding to the measured resistance into the independent variable of the mapping relationship y = f(x), and obtaining the value of the dependent variable as the theoretical resistance corresponding to the measured resistance.

[0112] In this exemplary embodiment, the plurality of measured resistors can form a first vector, and the plurality of theoretical resistors can form a second vector; the corresponding theoretical resistors and measured resistors can be located at the same position in the two vectors respectively. The first parameter can be any one of the Minkowski distance, Euclidean distance, Manhattan distance, and Canberra distance between the first vector and the second vector.

[0113] In this exemplary embodiment, the first threshold can be set to different values ​​depending on the algorithm of the first parameter.

[0114] In this exemplary embodiment, obtaining the mapping relationship between the resistance and temperature of a fully fused anti-fuse may include:

[0115] Provide a fully fused anti-fuse wire;

[0116] Obtain the measured resistance of the fully fused antifuse at different temperatures;

[0117] Establish a functional model of the measured resistance and temperature of the fully fused anti-fuse, wherein the functional model includes at least one undetermined constant;

[0118] The undetermined constant is obtained based on the measured resistance and temperature of at least one set of the fully fused antifuse wires.

[0119] In this exemplary embodiment, the function model is:

[0120] Y = aX + b, where temperature is the independent variable, measured resistance is the dependent variable, and a and b are the undetermined constants.

[0121] In this exemplary embodiment, the measured resistance of the fully fused anti-fuse wire at two different temperatures can be obtained. The temperature is substituted into the independent variable of the function model, and the measured resistance is substituted into the dependent variable of the function model. The two sets of temperatures and measured resistances can yield two sets of equations with a and b as unknowns. Solving these equations can yield the undetermined constants a and b, that is, the mapping relationship between the resistance and temperature of the fully fused anti-fuse wire is obtained: Y = aX + b.

[0122] In this exemplary embodiment, the detection method can also obtain multiple sets of different undetermined constants a and b by detecting the measured resistance of the fully fused anti-fuse under different temperature combinations, and select the optimal undetermined constant from the multiple sets of undetermined constants. For example, this detection method can obtain the measured resistance of a fully fused antifuse wire at N different temperatures, where N is a positive integer greater than 3; select multiple different temperature combinations and their corresponding measured resistances from the N temperature and measured resistance sets, with each temperature combination including two different temperatures; obtain different proxy constants based on different temperature combinations and their corresponding measured resistances; for each temperature combination, obtain the theoretical resistance corresponding to the remaining N-2 different temperatures according to the function model, that is, substitute the remaining N-2 different temperatures into the independent variable of the function model, and obtain the theoretical resistance as the dependent variable of the function model; obtain a second parameter based on the N-2 theoretical resistances and their corresponding N-2 measured resistances, the second parameter characterizing the difference between the theoretical resistance and the measured resistance in the fully fused antifuse wire, the larger the second parameter, the greater the difference between the theoretical resistance and the measured resistance in the fully fused antifuse wire; obtain the undetermined constant corresponding to the minimum value among multiple second parameters as the optimal undetermined constant, and use the function model corresponding to the optimal undetermined constant as the mapping relationship between the resistance and temperature of the fully fused antifuse wire.

[0123] In this exemplary embodiment, the plurality of measured resistors in the fully fused antifuse can form a third vector, and the plurality of theoretical resistors in the fully fused antifuse can form a fourth vector; the corresponding theoretical resistors and measured resistors can be located at the same position in the two vectors respectively. The second parameter can be any one of the Minkowski distance, Euclidean distance, Manhattan distance, and Canberra distance between the third vector and the fourth vector.

[0124] It should be understood that in other exemplary embodiments, the function model can also be other architectures, such as exponential functions, logarithmic functions, multiplicative functions, etc. The number of undetermined constants can also be other numbers, and the number of equations in the system of equations required to obtain the undetermined constants needs to be the same as the number of undetermined constants.

[0125] In this exemplary embodiment, obtaining the measured resistance of the antifuse under test at multiple different temperatures may include:

[0126] The measured resistance of the antifuse under test at the first temperature is taken as the first resistance;

[0127] The measured resistance of the antifuse wire under test at a second temperature is obtained as the second resistance, wherein the first temperature is greater than the second temperature;

[0128] Determining the correlation between the measured resistance and temperature of the antifuse under test can include:

[0129] Compare the values ​​of the first resistor and the second resistor;

[0130] When the first resistance is greater than the second resistance, it is determined that the measured resistance of the antifuse under test is positively correlated with the temperature.

[0131] This exemplary embodiment only compares the resistance of the antifuse wire at two different temperatures, which greatly simplifies the antifuse wire detection process.

[0132] In this exemplary embodiment, the first temperature can be greater than or equal to 80 degrees Celsius, and the second temperature can be less than or equal to 40 degrees Celsius. For example, the first temperature can be equal to 80 degrees Celsius, 90 degrees Celsius, 98 degrees Celsius, 110 degrees Celsius, etc. The second temperature can be equal to 40 degrees Celsius, 30 degrees Celsius, 25 degrees Celsius, 15 degrees Celsius, etc.

[0133] According to actual tests, the failure rate of the detection method provided in this exemplary embodiment to detect incomplete fuse blowing is only 0.03%, while the failure rate of the detection method in related technologies to detect incomplete fuse blowing is 5%.

[0134] According to one aspect of this disclosure, a method for blowing an anti-fuse is provided, the method comprising:

[0135] The anti-fuse wire under test is blown off.

[0136] The antifuse to be tested is subjected to a detection action, the detection action including the antifuse detection method described above;

[0137] If the detection action cannot determine that the anti-fuse under test is completely blown, the blow-off action and detection action are repeated for the anti-fuse under test.

[0138] like Figure 7 The diagram shown is a logic diagram of an exemplary embodiment of the antifuse blowing method of this disclosure. The blowing method may include: blowing the antifuse under test; detecting a first resistance R1 of the antifuse under test at a first temperature and a second resistance R2 at a second temperature, wherein the resistance at the first temperature is greater than the resistance at the second temperature; when the first resistance R1 is greater than the second resistance R2, determining that the antifuse under test is completely blown; otherwise, re-blowing the antifuse under test.

[0139] like Figure 8The diagram shown is a logic diagram of another exemplary embodiment of the antifuse blowing method of this disclosure. The blowing method may include: blowing the antifuse under test; detecting a first resistance R1 of the antifuse under test at a first temperature and a second resistance R2 at a second temperature, wherein the resistance at the first temperature is greater than the resistance at the second temperature; when both the first resistance R1 and the second resistance R2 are less than a threshold resistance Rx, comparing the magnitudes of the first resistance R1 and the second resistance R2; otherwise, blowing the antifuse under test again; when the first resistance is greater than the second resistance, determining that the antifuse under test is completely blown; otherwise, blowing the antifuse under test again.

[0140] According to one aspect of this disclosure, a chip is provided, the chip including an antifuse, the antifuse in the chip being melted by the antifuse melting method described above. This chip can be a dynamic random access memory (DRAM).

[0141] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

[0142] The accompanying drawings in this disclosure only illustrate the structures involved in this disclosure; other structures can be referred to with common design. Unless otherwise specified, the embodiments and features described in these embodiments can be combined to obtain new embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this disclosure without departing from the spirit and scope of this disclosure, and all such modifications and substitutions should be covered within the scope of the claims of this disclosure.

[0143] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is defined only by the appended claims.

Claims

1. A method for detecting antifuse wires, characterized in that, The detection method includes: Obtain the measured resistance of the antifuse under test at multiple different temperatures; Determine the correlation between the measured resistance and temperature of the antifuse under test; Determine whether the anti-fuse under test is completely melted based on the correlation between the measured resistance and temperature of the anti-fuse under test; Specifically, when the measured resistance of the anti-fuse under test is positively correlated with the temperature, it is determined that the anti-fuse under test is completely melted. Specifically, when the measured resistance of the anti-fuse under test is negatively correlated with the temperature, it is determined that the anti-fuse under test is not completely melted. When the measured resistance of the antifuse under test is neither positively nor negatively correlated with the temperature, the measured resistance of the antifuse under test is re-acquired at multiple different temperatures, and the correlation between the measured resistance and the temperature of the antifuse under test is re-determined.

2. The antifuse detection method according to claim 1, characterized in that, The process of obtaining the measured resistance of the antifuse under test at multiple different temperatures includes: The measured resistance of the antifuse under test at the first temperature is taken as the first resistance; The measured resistance of the antifuse wire under test at a second temperature is obtained as the second resistance, wherein the first temperature is greater than the second temperature; Determining the correlation between the measured resistance and temperature of the antifuse under test includes: Compare the values ​​of the first resistor and the second resistor; When the first resistance is greater than the second resistance, it is determined that the measured resistance of the antifuse under test is positively correlated with the temperature.

3. The antifuse detection method according to claim 2, characterized in that, The first temperature is greater than or equal to 80 degrees Celsius, and the second temperature is less than or equal to 40 degrees Celsius.

4. The antifuse detection method according to claim 1, characterized in that, The detection method further includes: Compare the measured resistance of the antifuse under test with the preset resistance at different temperatures; When the measured resistance of the antifuse under test is greater than the preset resistance, it is determined that the antifuse under test is not completely melted. When the measured resistance of the anti-fuse under test is less than the preset resistance, the test anti-fuse under test is then judged to be completely melted based on the correlation between the measured resistance of the anti-fuse under test and the temperature.

5. The antifuse detection method according to claim 1, characterized in that, The detection method further includes: Obtain the mapping relationship between resistance and temperature when the anti-fuse is fully fused; The theoretical resistance corresponding to the measured resistance of the antifuse to be tested is obtained according to the mapping relationship, wherein the corresponding measured resistance and theoretical resistance correspond to the same temperature; A first parameter is obtained based on a plurality of measured resistances and a plurality of theoretical resistances. The first parameter characterizes the difference between the theoretical resistance and the measured resistance. The larger the first parameter is, the greater the difference between the theoretical resistance and the measured resistance. When the first parameter is greater than the first threshold, it is determined that the anti-fuse wire under test is not completely melted; When the first parameter is less than the first threshold, the correlation between the measured resistance and temperature of the anti-fuse under test is used to determine whether the anti-fuse under test is completely melted.

6. The antifuse detection method according to claim 5, characterized in that, To obtain the mapping relationship between the resistance and temperature of a fully fused anti-fuse, including: Provide a fully fused anti-fuse wire; Obtain the measured resistance of the fully fused antifuse at different temperatures; Establish a functional model of the measured resistance and temperature of the fully fused anti-fuse, wherein the functional model includes at least one undetermined constant; The undetermined constant is obtained based on the measured resistance and temperature of at least one set of the fully fused antifuse wires.

7. The antifuse detection method according to claim 6, characterized in that, The function model is as follows: Y = aX + b, where the temperature is the independent variable, the measured resistance is the dependent variable, and a and b are the undetermined constants.

8. The antifuse detection method according to claim 5, characterized in that, The plurality of measured resistors form a first vector, and the plurality of theoretical resistors form a second vector; The first parameter is any one of the following distances between the first vector and the second vector: Minkowski distance, Euclidean distance, Manhattan distance, and Canberra distance.

9. The antifuse detection method according to any one of claims 1-8, characterized in that, The minimum temperature difference between the different temperatures is greater than or equal to 10 degrees Celsius.

10. The antifuse detection method according to any one of claims 1-8, characterized in that, The detection method further includes heating the antifuse wire to be tested to different temperatures; Heating the antifuse wire to be tested to different temperatures includes: The antifuse to be tested is placed in an environment with a preset temperature to heat the antifuse to the preset temperature.

11. The antifuse detection method according to any one of claims 1-8, characterized in that, The detection method further includes heating the antifuse wire to be tested to different temperatures; Heating the antifuse wire to be tested to different temperatures includes: The anti-fuse to be tested is placed in a current path, and the anti-fuse to be tested is heated to different temperatures by the current.

12. The antifuse detection method according to any one of claims 1-8, characterized in that, Obtaining the measured resistance of the antifuse under test at multiple different temperatures includes: The antifuse to be tested and a known resistor are connected in series between the first power supply terminal and the second power supply terminal, wherein the voltage at the first power supply terminal is greater than the voltage at the second power supply terminal. The measured resistance of the antifuse under test is obtained based on the voltage at the node between the antifuse under test and the known resistor.

13. A method for blowing an anti-fuse, characterized in that, include: The anti-fuse wire under test is blown off. The antifuse to be tested is subjected to a detection action, the detection action comprising the antifuse detection method according to any one of claims 1-12; If the detection action cannot determine that the anti-fuse under test is completely blown, the blow-off action and detection action are repeated for the anti-fuse under test.

14. A chip, characterized in that, The chip includes an antifuse, which is melted by the antifuse melting method according to claim 13.

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