Circuit Detection Method

Abstract

A circuit detection method includes: providing a storage circuit to be tested; performing a first aging test on the storage circuit to be tested; after the first aging test, performing a reliability test on the storage circuit to be tested to obtain a first minimum operating voltage V cc1 ; performing a second aging test on the storage circuit to be tested; after the second aging test, reading the first minimum operating voltage V cc1 to perform a number of first cycle tests to obtain a second minimum operating voltage V cc2 . The method of the nth first cycle test includes: when the test voltage V (n‑1)t1 of the (n - 1)th first cycle test is used to detect that the function of the storage circuit to be tested is unqualified, detecting with the test voltage V nt1 of the nth first cycle test, where n is a natural number greater than or equal to 1, 0 < V cc1 ≤ V (n‑1)t1 < V nt1 , and when n = 1, V (n‑1)t1 = V cc1 . Through the circuit detection method, the detection efficiency of the minimum operating voltage of the storage circuit to be tested is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and more particularly to a circuit detection method. Background Art

[0002] With the rapid development of integrated circuit manufacturing technology, the size of semiconductor devices in integrated circuits has been continuously reduced, enabling the operating speed of the entire integrated circuit to be effectively improved.

[0003] Generally, in an advanced process platform, product-level reliability testing of SRAM is used as one of the reliability detections of integrated circuits. Specifically, the product-level reliability testing of SRAM includes an aging test and a final test (hereinafter referred to as FT) after the aging test. Through FT, various parameters of SRAM can be obtained. Among them, the minimum operating voltage of SRAM, that is, the minimum voltage at which SRAM can read and write normally, is a key parameter used to characterize the degradation of SRAM after the aging test.

[0004] However, since after each aging test, the same relatively large preset minimum operating voltage is used as the starting voltage, and the function of the SRAM under test is gradually detected from high voltage to low voltage (by step) to determine whether it is qualified (Pass / Fail) to obtain the minimum operating voltage of the SRAM under test after each aging test. Therefore, the number of cycle tests after each aging test is relatively large and the detection time is relatively long. Correspondingly, after multiple aging tests, the total number of cycle tests required is also relatively large and the total detection duration is also very long. As a result, the detection efficiency of the minimum operating voltage of the SRAM under test is relatively poor. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a circuit detection method to improve the detection efficiency of the minimum operating voltage of the storage circuit under test.

[0006] To solve the above technical problem, the technical solution of the present invention provides a circuit detection method, including: providing a storage circuit under test; performing a first aging test on the storage circuit under test; after the first aging test, performing a reliability test on the storage circuit under test to obtain a first minimum operating voltage V cc1 ; performing a second aging test on the storage circuit under test; after the second aging test, reading the first minimum operating voltage V cc1 to perform a number of first cycle tests to obtain a second minimum operating voltage V cc2 wherein the method of the nth first cycle test includes: when using the test voltage V of the (n - 1)th first cycle test (n-1)t1When the function of the storage circuit to be tested is detected to be unqualified, the test voltage V of the nth first-cycle test is used for detection, where n is a natural number greater than or equal to 1, and 0 < V nt1 ≤ V cc1 <V (n-1)t1 <V nt1 , and when n = 1, V (n-1)t1 = V cc1 .

[0007] Optionally, the method of the nth first-cycle test further includes: obtaining the test voltage V according to the preset variable voltage V i , V nt1 > 0, and V i = V nt1 +(n × V cc1 ). i )

[0008] Optionally, the method of performing several first-cycle tests further includes: comparing the magnitudes of the test voltage V nt1 and the preset voltage V z , and when V nt1 > V z , ending the first-cycle test and prompting that the test voltage V nt1 exceeds the preset maximum value of the second minimum operating voltage V cc2 .

[0009] Optionally, the method of performing several first-cycle tests further includes: when the function of the storage circuit to be tested is detected to be qualified using the test voltage V nt1 , ending the first-cycle test, and obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 .

[0010] Optionally, obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 = V nt1 .

[0011] Optionally, the method of ending the first-cycle test and obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 includes: performing several second-cycle tests on the storage circuit to be tested, where the method of the mth second-cycle test includes: when the function of the storage circuit to be tested is detected to be qualified using the test voltage V of the (m - 1)th second-cycle test (m-1)t2 , detecting using the test voltage V of the mth time mt2 , m is a natural number greater than or equal to 1, and V mt2 <V (m-1)t2 ≤ V nt1, and when m = 1, V (m-1)t2 = V nt1 .

[0012] Optionally, the method for performing a number of second cycle tests includes: when V mt2 ≤ V (n-1)t1 , or when the test voltage V mt2 detects that the storage circuit under test is unqualified, end the second cycle test, and obtain the second minimum operating voltage V cc2 = V (m-1)t2 .

[0013] Optionally, the method for the m-th second cycle test further includes: obtaining the test voltage V ii according to the preset change voltage V mt2 , where V ii > 0, V mt2 = V nt1 -(m × V ii ).

[0014] Optionally, the method for obtaining the second minimum operating voltage V cc2 further includes: when the function of the storage circuit under test is qualified by using the first minimum operating voltage V cc1 , the second minimum operating voltage V cc2 = V cc1 .

[0015] Optionally, the method for obtaining the second minimum operating voltage V cc2 further includes: when the function of the storage circuit under test is qualified by using the first minimum operating voltage V cc1 , performing a number of third cycle tests on the storage circuit under test, where the method for the p-th third cycle test includes: when the function of the storage circuit under test is qualified by using the test voltage V (p-1)t3 of the (p - 1)-th third cycle test, using the test voltage V pt3 of the p-th third cycle test for detection, p is a natural number greater than or equal to 1, 0 < V pt3 < V (p-1)t3 ≤ V cc1 , and when p = 1, V (p-1)t3 = V cc1 .

[0016] Optionally, the method for performing a number of third cycle tests further includes: when the function of the storage circuit under test is unqualified by using the test voltage V pt3 , end the third cycle test, and obtain the second minimum operating voltage V cc2 = V (p-1)t3 .

[0017] Optionally, the method for the p-th third cycle test further includes: according to a preset variable voltage V iii obtain a test voltage V pt3 , where V iii > 0, V pt3 = V cc1 -(p × V iii ).

[0018] Optionally, the method for obtaining the first minimum operating voltage V cc1 includes: after the first aging test, performing a plurality of fourth cycle tests on the storage circuit under test, where the method for the k-th fourth cycle test includes: when the function of the storage circuit under test is detected to be qualified using the test voltage V (k-1)t4 of the (k - 1)-th fourth cycle test, detecting using the test voltage V kt4 of the k-th fourth cycle test, k is a natural number greater than or equal to 1, 0 < V kt4 < V (k-1)t4 , and when k = 1, V (k-1)t4 is the preset voltage V y .

[0019] Optionally, the method for the k-th fourth cycle test further includes: according to a preset variable voltage V ⅳ and a preset voltage V y obtain a test voltage V kt4 , where V ⅳ > 0, V kt4 = V y -(k × V ⅳ ).

[0020] Optionally, the method for obtaining the first minimum operating voltage V cc1 further includes: when the function of the storage circuit under test is detected to be unqualified using the test voltage V kt4 , end the fourth cycle test, and obtain the first minimum operating voltage V cc1 = V (k-1)t4 .

[0021] Optionally, the function of the storage circuit under test includes a data storage function or a data reading function.

[0022] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0023] In the circuit detection method provided by the technical solution of the present invention, the total target duration is segmented, and several aging tests with a duration less than the total target duration are performed to obtain the circuit parameters after each aging test. The first aging test refers to the previous aging test, and the second aging test refers to the current aging test. As the number of aging tests increases, the minimum operating voltage of the storage circuit to be tested tends to increase. Since the method for the nth first cycle test includes: when the function of the storage circuit to be tested is detected to be unqualified using the test voltage V of the (n - 1)th first cycle test (n-1)t1 for detection, using the test voltage V of the nth first cycle test nt1 for detection, where 0 < V cc1 ≤ V (n-1)t1 < V nt1 , and when n = 1, V (n-1)t1 = V cc1 , therefore, by utilizing the first minimum operating voltage V cc1 , the detection efficiency of the second minimum operating voltage V cc2 is improved, and thus, the detection efficiency of the minimum operating voltage of the storage circuit to be tested is improved. Specifically, compared with the previous aging test (the first aging test), after the current aging test (the second aging test), generally, the change in the minimum operating voltage measured by the storage circuit to be tested in the reliability test is small, that is, the difference between the second minimum operating voltage V cc2 and the first minimum operating voltage V cc1 is small. Therefore, by using the first minimum operating voltage V cc1 as the starting test voltage for detecting the second minimum operating voltage V cc2 , the number of first cycle tests for detecting the second minimum operating voltage V cc2 each time can be reduced, and the second minimum operating voltage V cc2 can be quickly approached and obtained. Thus, the detection efficiency of the second minimum operating voltage V cc2 after each second aging test is improved, and the detection duration of the second minimum operating voltage V cc2 after each second aging test is saved. Therefore, the detection efficiency of the minimum operating voltage of the storage circuit to be tested is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic flowchart of the circuit monitoring method according to an embodiment of the present invention;

[0025] Figure 2 is a schematic flowchart of the first execution of step S220 in an embodiment of the present invention;

[0026] Figure 3 is Figure 2 a schematic diagram of the test voltage and test duration of the fourth cycle test in

[0027] Figure 4 is Figure 1 The flow diagram of step S400 in

[0028] Figure 5 is Figure 4 The diagram of the test voltage and test duration of the first cycle test in

[0029] Figure 6 This is in another embodiment of the present invention. According to the test voltage V nt1 to obtain the second minimum operating voltage V cc2 The flow diagram is as follows;

[0030] Figure 7 is Figure 1 The flow diagram of step S500 in Detailed implementation manners

[0031] As described in the background art, since after each aging test, the same relatively large preset minimum operating voltage is used as the starting voltage, and the function of the SRAM under test is gradually detected from a high voltage to a low voltage (by step) to determine whether it is qualified (Pass / Fail) to obtain the minimum operating voltage of the SRAM under test after each aging test. Therefore, the number of cycle tests after each aging test is relatively large and the detection time is relatively long. Correspondingly, after multiple aging tests, the total number of cycle tests required is also relatively large and the total detection duration is also very long. As a result, the detection efficiency of the minimum operating voltage of the SRAM under test is relatively low.

[0032] To solve the above technical problem, an embodiment of the present invention provides a circuit detection method. After the second aging test, several first cycle tests are performed to obtain the second minimum operating voltage V cc2 , and the method of the nth first cycle test includes: when the function of the storage circuit under test is detected to be unqualified using the test voltage V (n-1)t1 of the (n - 1)th first cycle test, the detection is performed using the test voltage V nt1 of the nth first cycle test. Therefore, through the circuit detection method, the detection efficiency of the minimum operating voltage of the storage circuit under test is improved.

[0033] To make the above objects, features, and beneficial effects of the present invention more obvious and understandable, the following will describe the specific embodiments of the present invention in detail with reference to the accompanying drawings.

[0034] Figure 1 This is the flow diagram of the circuit detection method according to an embodiment of the present invention.

[0035] Please refer to Figure 1 , the circuit detection method includes:

[0036] Step S100: Provide a storage circuit to be tested;

[0037] Step S210: Conduct a first aging test on the storage circuit to be tested;

[0038] Step S220: After the first aging test, conduct a reliability test on the storage circuit to be tested to obtain the first minimum operating voltage V cc1 ;

[0039] Step S300: Conduct a second aging test on the storage circuit to be tested;

[0040] Step S400: After the second aging test, read the first minimum operating voltage V cc1 to conduct a number of first cycle tests to obtain the second minimum operating voltage V cc2 。

[0041] In this embodiment, the total target duration is segmented, and a number of aging tests with a duration less than the total target duration are conducted to obtain the circuit parameters after each aging test.

[0042] It should be noted that the first aging test refers to the previous aging test, and the second aging test refers to the current aging test. Therefore, starting from the second of the several aging tests, each aging test can be used as the second aging test in Step S300. Correspondingly, the reliability test can be conducted on the storage circuit to be tested through Step S400 to obtain the corresponding second minimum operating voltage V cc2 。 At the same time, as the number of aging tests increases, the minimum operating voltage of the storage circuit to be tested tends to increase.

[0043] Please refer to Figure 2 , Figure 2 is a schematic flow chart of the first execution of Step S220 in an embodiment of the present invention. After the first aging test among several aging tests, that is, after the first first aging test, a reliability test is conducted on the storage circuit to be tested to obtain the first minimum operating voltage V cc1 The method for obtaining

[0044] Step S221: After the first aging test, conduct a number of fourth cycle tests on the storage circuit to be tested;

[0045] Step S222: The method for the kth fourth cycle test includes: when the test voltage V of the (k - 1)th fourth cycle test (k-1)t4 detects that the function of the storage circuit to be tested is qualified, use the test voltage V of the kth fourth cycle test kt4 for detection, where k is a natural number greater than or equal to 1, and 0 < Vkt4 <V (k-1)t4 , and when k = 1, V (k-1)t4 is the preset voltage V y ;

[0046] Step S223, when the function of the storage circuit under test is detected to be unqualified using the test voltage V kt4 , end the fourth cycle test, and obtain the first minimum operating voltage V cc1 = V (k-1)t4 .

[0047] For ease of understanding, taking k = 3 as an example, when the function of the storage circuit under test is detected to be unqualified using the test voltage V kt4 , the method of obtaining the first minimum operating voltage V cc1 after the first aging test is described.

[0048] Specifically, provide the preset voltage V y , and detect the function of the storage circuit under test using the test voltage V 0t4 , where V 0t4 is the preset voltage V y and 0 < V y .

[0049] Using the test voltage V 0t4 to detect that the function of the storage circuit under test is qualified. Therefore, continue to detect the function of the storage circuit under test using the test voltage V 1t4 , where V 1t4 is a test voltage less than V 0t4 . Using the test voltage V 1t4 to detect that the function of the storage circuit under test is qualified. Therefore, continue to detect the function of the storage circuit under test using the test voltage V 2t4 , where V 2t4 is a test voltage less than V 1t4 . Similarly, using the test voltage V 2t4 to detect that the function of the storage circuit under test is qualified. Therefore, continue to detect the function of the storage circuit under test using the test voltage V 3t4 , where V 3t4 is a test voltage less than V 2t4 .

[0050] At this time, using the test voltage V 3t4 to detect that the function of the storage circuit under test is unqualified. Therefore, end the fourth cycle test. At the same time, the first minimum operating voltage V cc1 = V 3t4 .

[0051] It can be seen from this that after the first aging test, by providing a relatively large preset voltage Vy and, based on the preset voltage V y , by gradually decreasing the voltage from a high voltage to a low voltage, the method of successively detecting whether the function of the storage circuit to be tested is qualified is used, and a total of duration t0 is used for several fourth-cycle tests (as shown in Figure 3 ), and the corresponding first minimum operating voltage V cc1 is obtained.

[0052] In this embodiment, the method of the k-th fourth-cycle test further includes: obtaining a test voltage V ⅳ according to the preset variable voltage V y and the preset voltage V kt4 , where V ⅳ >0, and V kt4 = V y - (k×V ⅳ ). Thus, as k increases, the test voltage V kt4 gradually decreases based on the preset voltage V y , so as to successively detect whether the function of the storage circuit to be tested is qualified from a high voltage to a low voltage through several fourth-cycle tests.

[0053] For ease of understanding, an example with k = 3 is used for illustration. When k = 3, V 3t4 = V y - (3×V ⅳ ).

[0054] Please refer to Figure 4 , Figure 4 which is Figure 1 the flow schematic diagram of step S400 in

[0055] Step S410, the method of the n-th first-cycle test includes: when it is detected that the function of the storage circuit to be tested is unqualified using the test voltage V (n-1)t1 of the (n - 1)-th first-cycle test, detecting with the test voltage V nt1 of the n-th first-cycle test,

[0056] where n is a natural number greater than or equal to 1, 0 < V cc1 ≤ V (n-1)t1 < V nt1 , and when n = 1, V (n-1)t1 = V cc1 .

[0057] Since the method of the n-th first-cycle test includes: when it is detected that the function of the storage circuit to be tested is unqualified using the test voltage V (n-1)t1 of the (n - 1)-th first-cycle test, detecting with the test voltage Vnt1 Perform a detection, 0 < V cc1 ≤ V (n-1)t1 <V nt1 , and when n = 1, V (n-1)t1 = V cc1 , therefore, by utilizing the first minimum operating voltage V cc1 , the detection efficiency of the second minimum operating voltage V cc2 is improved, thereby improving the detection efficiency of the minimum operating voltage of the storage circuit to be tested.

[0058] Specifically, compared with the previous aging test (the first aging test), after the current aging test (the second aging test), generally, the change in the minimum operating voltage measured in the reliability test of the storage circuit to be tested is small, that is, the difference between the second minimum operating voltage V cc2 and the first minimum operating voltage V cc1 is small. Therefore, by using the first minimum operating voltage V cc1 as the starting test voltage for detecting the second minimum operating voltage V cc2 , the number of the first cycle tests for each detection of the second minimum operating voltage V cc2 can be reduced, and the second minimum operating voltage V cc2 can be quickly approached and obtained, thereby improving the detection efficiency of the second minimum operating voltage V cc2 after the second aging test at a low level, saving the detection duration of the second minimum operating voltage V cc2 after each second aging test, thereby improving the detection efficiency of the minimum operating voltage of the storage circuit to be tested.

[0059] Please continue to refer to Figure 4 , and the method for performing several first cycle tests further includes:

[0060] Step S420, when the function of the storage circuit to be tested is qualified when detected by the test voltage V nt1 , end the first cycle test, and obtain the second minimum operating voltage V nt1 according to the test voltage V cc2 = V nt1 . For example, when the function of the storage circuit to be tested is qualified when detected by the test voltage V 4t1 (when n = 4), end the first cycle test, and the second minimum operating voltage V cc2 = V 4t1 .

[0061] In this embodiment, the method for the nth first cycle test further includes: obtaining the test voltage V i according to the preset change voltage V nt1 , V i > 0, and, Vnt1 = V cc1 + (n × V i ).

[0062] For ease of understanding, an example with n = 4 is used for illustration. When n = 4, V 4t1 = V cc1 + (4 × V i ).

[0063] Thus, in several first cycle tests after the second aging test (the current aging test), with the first minimum operating voltage V cc1 as the starting test voltage, and as n increases, based on the preset variable voltage V i , by using a gradually increasing test voltage V nt1 , from low voltage to high voltage, the functionality of the storage circuit under test is gradually and successively detected for compliance. And, a total of duration t1 is used for several first cycle tests (as shown in Figure 5 ), and the corresponding second minimum operating voltage V cc2 is obtained.

[0064] In this embodiment, the functionality of the storage circuit under test includes a data storage function or a data reading function. That is, the detection object in the circuit detection method can be the data storage function of the storage circuit under test, or the data storage function of the storage circuit under test.

[0065] It should be noted that when detecting the data storage function of the storage circuit under test by the circuit detection method, the functionality of the storage circuit under test being qualified means that the storage circuit under test can correctly store data; the functionality of the storage circuit under test being unqualified means that the storage circuit under test cannot store data, or the error in the stored data exceeds the preset standard.

[0066] Similarly, when detecting the data reading function of the storage circuit under test by the circuit detection method, the functionality of the storage circuit under test being qualified means that the storage circuit under test can correctly read data; the functionality of the storage circuit under test being unqualified means that the storage circuit under test cannot read data, or the error in the read data exceeds the preset standard.

[0067] Specifically, by adopting the circuit detection method, the data storage function and data reading function of the storage circuit to be tested are respectively detected, so that the minimum working voltage required for data storage of the storage circuit to be tested after the current aging test can be obtained, and the minimum working voltage required for data reading of the storage circuit to be tested after the current aging test can be obtained. On this basis, by selecting the larger one of the minimum working voltage during data storage and the minimum working voltage during data reading, the minimum working voltage required for the storage circuit to be tested to be able to perform data storage and data reading simultaneously after the current aging test can also be obtained, that is, after the current aging test, the minimum working voltage when the data storage function and data reading function of the storage circuit to be tested are both qualified.

[0068] For example, after the current aging test, by adopting the circuit detection method, when detecting the data storage function of the storage circuit to be tested, the corresponding minimum working voltage obtained is 0.48V. By adopting the circuit detection method, when detecting the data reading function of the storage circuit to be tested, the corresponding minimum working voltage obtained is 0.47V. Then, after the current aging test, the minimum working voltage when the data storage function and data reading function of the storage circuit to be tested are both qualified is 0.48V.

[0069] Please continue to refer to Figure 4 , the method for performing a plurality of first cycle tests further includes: step S430, comparing the test voltage V nt1 and the preset voltage V z , and when V nt1 >V z , ending the first cycle test and prompting that the test voltage V nt1 exceeds the preset maximum value of the second minimum working voltage V cc2 .

[0070] Specifically, in this embodiment, for the second minimum working voltage V cc2 corresponding to each second aging test, there is a preset maximum value, that is, the preset voltage V z . Generally, when the test voltage V nt1 exceeds the preset voltage V z , it indicates that after the second aging test, the function of the storage circuit to be tested cannot be qualified within the preset range of the second minimum working voltage, that is, the reliability of the storage circuit to be tested is poor and needs to be improved. On this basis, since when V nt1 >V z , the first cycle test is ended. Therefore, during the first cycle test, unnecessary detection times and detection durations can be reduced, thereby better improving the detection efficiency of the circuit detection method.

[0071] In this embodiment, before detecting the function of the storage circuit under test using the test voltage V nt1 the magnitudes of the test voltage V nt1 and the preset voltage V z are compared. Thus, when V nt1 > V z , the nth first-cycle test is directly not performed. Thus, during the first-cycle test, the number of unnecessary detections and the detection duration are further reduced, thereby better improving the detection efficiency of the circuit detection method.

[0072] In other embodiments, after detecting the function of the storage circuit under test using the test voltage V nt1 the magnitudes of the test voltage V nt1 and the preset voltage V z are compared. Thus, when V nt1 > V z , the (n + 1)th first-cycle test is not performed, and regardless of whether the function of the storage circuit under test detected by the test voltage V nt1 is qualified, it is prompted that the test voltage V nt1 exceeds the preset maximum value of the second minimum operating voltage V cc2 .

[0073] In another embodiment, different from the method of obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 in step S420 of this embodiment. Figure 6 It is a schematic flowchart of obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 in another embodiment of the present invention.

[0074] Please refer to Figure 6 , end the first-cycle test, and the method of obtaining the second minimum operating voltage V nt1 according to the test voltage V cc2 includes:

[0075] Step S441, performing a number of second-cycle tests on the storage circuit under test;

[0076] Step S442, the method of the mth second-cycle test includes: when the function of the storage circuit under test is detected to be qualified using the test voltage V (m-1)t2 of the (m - 1)th second-cycle test, detecting using the test voltage V mt2 , m is a natural number greater than or equal to 1, V mt2 < V (m-1)t2 ≤ V nt1 , and when m = 1, V (m-1)t2 = V nt1 ;

[0077] Step S443, when V mt2 ≤V (n-1)t1 or, when the test voltage V mt2 detects that the memory circuit under test is unqualified, end the second loop test, and obtain the second minimum operating voltage V cc2 =V (m-1)t2 .

[0078] Specifically, in another embodiment, when using the test voltage V nt1 to detect that the function of the memory circuit under test is qualified, continue to detect whether the function of the memory circuit under test is qualified through several second loop tests. Specifically, use the test voltage V nt1 as the starting test voltage, and between the test voltage V nt1 and the test voltage V (n-1)t1 , gradually detect whether the function of the memory circuit under test is qualified from high voltage to low voltage. Thus, a smaller second minimum operating voltage V cc2 can be detected, further improving the detection accuracy of the second minimum operating voltage V cc2 .

[0079] In another embodiment, the method of the m-th second loop test further includes: obtaining the test voltage V ii according to the preset variable voltage V mt2 , where V ii >0, V mt2 =V nt1 -(m×V ii ).

[0080] Please continue to refer to Figure 1 , the method of obtaining the second minimum operating voltage V cc2 further includes: Step S500, when using the first minimum operating voltage V cc1 to detect that the function of the memory circuit under test is qualified, perform several third loop tests on the memory circuit under test.

[0081] Please refer to Figure 7 , Figure 7 is Figure 1 the flow diagram of step S500 in cc1 , when using the first minimum operating voltage V

[0082] Step S510, the method of the p-th third loop test includes: when using the test voltage V (p-1)t3 of the (p - 1)-th third loop test to detect that the function of the memory circuit under test is qualified, use the test voltage V of the p-th third loop testpt3 Perform a detection, where p is a natural number greater than or equal to 1, and 0 < V pt3 < V (p-1)t3 ≤ V cc1 , and when p = 1, V (p-1)t3 = V cc1 ;

[0083] Step S520, when the function of the storage circuit under test is detected to be unqualified using the test voltage V pt3 , end the third cycle test, and obtain the second minimum operating voltage V cc2 = V (p-1)t3 .

[0084] Specifically, in this embodiment, when the function of the storage circuit under test is detected to be qualified using the first minimum operating voltage V cc1 , continue to detect whether the function of the storage circuit under test is qualified through several third cycle tests.

[0085] It should be noted that although the minimum operating voltage of the storage circuit under test tends to increase as the number of aging tests increases. However, when the detection accuracy is poor, it is easy for the first minimum operating voltage V cc1 obtained through detection to deviate greatly and be greater than the actual minimum operating voltage of the storage circuit under test after the previous aging test.

[0086] In this embodiment, through step S510 and step S520, a test voltage V cc1 less than the test voltage V 1t3 is used as the starting test voltage, and the function of the storage circuit under test is gradually detected from high voltage to low voltage. Therefore, it is possible to effectively reduce the influence of the deviation of the first minimum operating voltage V cc1 on obtaining the second minimum operating voltage V cc2 , and further improve the detection accuracy of the second minimum operating voltage V cc2 .

[0087] In this embodiment, the method of the pth third cycle test further includes: obtaining the test voltage V iii according to the preset voltage change V pt3 , where V iii > 0, V pt3 = V cc1 -(p × V iii ).

[0088] In another embodiment, the method of obtaining the second minimum operating voltage V cc2 further includes: when the function of the storage circuit under test is detected to be qualified using the first minimum operating voltage V cc1 , the second minimum operating voltage Vcc2 = V cc1 Thus, the detection efficiency of the second minimum operating voltage V cc2 is improved.

[0089] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A circuit detection method, characterized in that, Including: Providing a storage circuit to be tested; Performing a first aging test on the storage circuit to be tested; After the first aging test, perform a reliability test on the memory circuit under test to obtain the first minimum operating voltage V cc1 ; Performing a second aging test on the storage circuit to be tested; After the second aging test, read the first minimum operating voltage V cc1 to perform a number of first cycle tests to obtain a second minimum operating voltage V cc2 , wherein the method of the nth first cycle test includes: When using the test voltage V of the (n - 1)-th first-cycle test （n-1）t1 to detect that the function of the memory circuit under test is unqualified, use the test voltage V of the n-th first-cycle test nt1 for detection, where n is a natural number greater than or equal to 1, 0 < V cc1 ≤ V （n-1）t1 <V nt1 , and when n = 1, V （n-1）t1 = V cc1 ; When the test voltage V nt1 is used to detect that the function of the memory circuit under test is qualified, the first cycle of testing is ended, and, according to the test voltage V nt1 the second minimum operating voltage V cc2 is obtained; Among them, according to the test voltage V nt1 obtain the second minimum operating voltage V cc2 , including: V cc2 =V nt1 ; or, perform several second cycle tests on the memory circuit under test, Wherein, the method of the m-th second cycle test includes: When the test voltage V of the (m - 1)-th second loop test is adopted （m-1）t2 and the function of the memory circuit under test is detected to be qualified, the test voltage V of the m-th is adopted mt2 for detection, where m is a natural number greater than or equal to 1, V mt2 <V （m-1）t2 ≤V nt1 , and when m = 1, V （m-1）t2 =V nt1 ; When V mt2 ≤ V （n-1）t1 or, when the test voltage V mt2 detects that the memory circuit under test is unqualified, end the second cycle of testing, and obtain the second minimum operating voltage V cc2 = V （m-1）t2 .

2. The circuit detection method according to claim 1, characterized in that, The method of the nth first cycle test further includes: according to a preset variable voltage V i obtain a test voltage V nt1 , V i > 0, and, V nt1 = V cc1 + (n × V i ).

3. The circuit detection method according to claim 1, characterized in that The method of performing a number of first cycle tests further includes: comparing the test voltage V nt1 and the preset voltage V z , and when V nt1 > V z , ending the first cycle test and prompting that the test voltage V nt1 exceeds the preset maximum value of the second minimum operating voltage V cc2 .

4. The circuit detection method according to claim 1, characterized in that The method of the m-th second cycle test further includes: according to a preset variable voltage V ii obtain a test voltage V mt2 , where V ii > 0, V mt2 = V nt1 - (m × V ii ).

5. The circuit detection method according to claim 1, wherein Method for obtaining the second minimum operating voltage V cc2 further includes: when the function of the memory circuit under test is qualified by using the first minimum operating voltage V cc1 , the second minimum operating voltage V cc2 = V cc1 .

6. The circuit detection method according to claim 1, wherein, Method for obtaining the second minimum operating voltage V cc2 further includes: when the function of the memory circuit under test is qualified by using the first minimum operating voltage V cc1 , performing a plurality of third cycle tests on the memory circuit under test, wherein the method of the p-th third cycle test includes: when the function of the memory circuit under test is qualified by using the test voltage V （p-1）t3 of the (p - 1)-th third cycle test, detecting by using the test voltage V pt3 of the p-th third cycle test, where p is a natural number greater than or equal to 1, 0 < V pt3 < V （p-1）t3 ≤ V cc1 , and when p = 1, V （p-1）t3 = V cc1 .

7. The circuit detection method according to claim 6, wherein, The method for performing a number of third cycle tests further includes: when the function of the memory circuit under test is detected to be unqualified using the test voltage V pt3 the third cycle test is ended, and the second minimum operating voltage V cc2 =V （p-1）t3 is obtained.

8. The circuit detection method according to claim 6, wherein The method of the p-th said third cycle test further includes: according to a preset variable voltage V iii obtaining a test voltage V pt3 , where V iii > 0, V pt3 = V cc1 - (p × V iii ).

9. The circuit detection method according to claim 1, wherein Method for obtaining the first minimum operating voltage V cc1 includes: after the first aging test, performing a number of fourth cycle tests on the memory circuit under test, wherein the method of the k-th fourth cycle test includes: when the test voltage V of the (k - 1)-th fourth cycle test is used （k-1）t4 to detect that the function of the memory circuit under test is qualified, using the test voltage V of the k-th fourth cycle test kt4 for detection, k is a natural number greater than or equal to 1, 0 < V kt4 < V （k-1）t4 , and when k = 1, V （k-1）t4 is the preset voltage V y .

10. The circuit detection method according to claim 9, wherein, The method for the k-th fourth cycle test further includes: obtaining a test voltage V ⅳ according to a preset variable voltage V y and a preset voltage V kt4 , where V ⅳ >0, and V kt4 = V y - (k × V ⅳ ).

11. The circuit detection method according to claim 9, wherein Method for obtaining the first minimum operating voltage V cc1 further includes: when the function of the memory circuit under test is detected to be unqualified by using the test voltage V kt4 , end the fourth cycle test, and obtain the first minimum operating voltage V cc1 =V （k-1）t4 .

12. The circuit detection method according to claim 1, wherein The functions of the storage circuit to be tested include a data storage function or a data reading function.

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