TWI864179B - Inspection device, inspection system and inspection method - Google Patents

Abstract

An inspection device that can shorten the time required for testing and improve the reliability of actual products. The inspection device (2A) includes: a test controller (13) that controls a boundary scanning test on a circuit substrate (100); and a system controller (11); the system controller (11) allows the test controller (13) to perform a boundary scanning test on the circuit substrate (100) when an environment forming device (3) applies a vibration stress with more than three degrees of freedom to the circuit substrate (100).

Description

Inspection device, inspection system and inspection method

The present invention relates to an inspection device, an inspection system and an inspection method, and in particular to an inspection device, an inspection system and an inspection method for performing a boundary scanning test on an inspection object.

One of the inspections of a circuit board with a semiconductor device that uses JTAG (Joint Test Action Group) is a well-known boundary scan test. In the boundary scan test, the main purpose is to check for soft solder joint defects of semiconductor devices assembled on the circuit board, or open circuit faults or short circuit faults of wiring between multiple semiconductor devices. In Japanese Patent Publication No. 2000-148528, a test system that uses an integrated circuit that uses JTAG as an object to perform a boundary scan test is disclosed.

Actual products shipped after mass production may be used in severe conditions exposed to various environmental factors such as vibration and temperature. However, when using the test system disclosed in Japanese Patent Publication No. 2000-148528, the actual product usage is not assumed when performing the boundary scanning test, so there is a problem of lower reliability of the actual product. In addition, in order to reduce the test cost, there is also a problem of shortening the time required for the test.

The purpose of the present invention is to provide an inspection device, an inspection system, and an inspection method that can shorten the time required for testing while improving the reliability of actual products.

An inspection device according to one aspect of the present invention is an inspection device that can be communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and includes: a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit; the main control unit allows the test control unit to perform the boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate.

1: Check the system

2,2A: Inspection device

3: Environment forming device

11: System controller

12: Cavity monitor

13: Test the controller

14: Memory Department

15: Display unit

16: Communications Department

17: Relay unit

18: Scanner unit

21: Communications Department

22: Environmental controller

23: Air conditioning room

24: Cavity

25:Frame

26: Blower

27: Heater

28: Spray nozzle

29: Piping

30: Valve

31: Tank

32: Vibrating table

33: Spring

34: Supporting components

35: Actuator

36: Vibration detector

37: Temperature detector

38:Fixers

40: Wires

41: Exhaust port

42: Air supply port

100: Circuit board

[Figure 1] is a diagram that briefly shows the structure of the inspection system of the embodiment of the present invention.

[Figure 2] is a block diagram that briefly shows the structure of the inspection device.

[Figure 3] is a block diagram that briefly shows the structure of the environment forming device.

[Figure 4] is a diagram showing the first example of the vibration stress application mode to the circuit board.

[Figure 5] is a diagram showing the second example of the vibration stress application mode to the circuit board.

[Figure 6] is a diagram showing the third example of the vibration stress application mode to the circuit board.

[Figure 7] is a diagram showing the fourth example of the vibration stress application mode to the circuit board.

[Figure 8] is a diagram showing the fifth example of the vibration stress application mode to the circuit board.

[Figure 9] is a diagram showing the first example of the execution timing of the boundary scanning test on the circuit board.

[Figure 10] is a diagram showing the second example of the execution timing of the boundary scanning test on the circuit board.

[Figure 11] is a diagram showing the third example of the execution timing of the boundary scanning test on the circuit board.

[Figure 12] is a diagram showing the fourth example of the execution timing of the boundary scanning test on the circuit board.

[Figure 13] is a block diagram that briefly shows the structure of the modified inspection device.

[Figure 14] is a diagram that briefly shows the structure of the scanner unit.

The following is a detailed description of the implementation of the present invention using drawings. Moreover, in different drawings, components with the same number represent the same or corresponding components.

FIG1 is a diagram schematically showing the structure of an inspection system 1 of an embodiment of the present invention. As shown in FIG1 , the inspection system 1 includes an inspection device 2 and an environment forming device 3 that are connected to each other so as to be able to communicate with each other. The environment forming device 3 is an environmental testing device that is used to perform environmental testing on a prototype product during the design and development stage of a product in process. However, the environment forming device 3 may also be a screening device that is used to perform screening testing on an actual product during pre-shipment testing of the product. The inspection device 2 is a device including a control unit that performs a boundary scanning test on the inspection object accommodated by the environment forming device 3. The inspection object is a circuit board with semiconductor devices that are applicable to JTAG (Joint Test Action Group). In the boundary scan test, the main purpose is to check for poor soft soldering of semiconductor devices assembled on the circuit board, or open circuit faults or short circuit faults in the wiring between multiple semiconductor devices.

FIG2 is a block diagram schematically showing the structure of the inspection device 2 (2A). As shown in the connection relationship of FIG2, the inspection device 2A includes a system controller 11 (main control unit), a cavity monitor 12, a test controller 13 (test control unit), a memory unit 14, a display unit 15, and a communication unit 16.

The test controller 13 is a controller for controlling the boundary scan test performed on the circuit substrate 100 (described in detail later) as the inspection object by the control from the system controller 11. The test controller 13 performs processing such as generating test data (test mode) and generating test clock in the boundary scan test. The test controller 13 is connected to the relay unit 17.

The system controller 11 includes a processor such as a CPU and a memory such as a ROM and a RAM, and summarizes the actions of the entire system to control it. The system controller 11 allows the test controller 13 to perform a boundary scanning test on the circuit substrate 100 when the environment forming device 3 applies a predetermined environmental stress to the circuit substrate 100.

The memory unit 14 is any memory device such as a semiconductor memory or a hard disk. The display unit 15 is any display device such as a liquid crystal display or an organic EL display. The system controller 11 and the cavity monitor 12 are connected to each other, for example, by an RS-232C cable. The system controller 11 and the test controller 13 are connected to each other, for example, by a USB cable. The communication unit 16 and the communication unit 21 (described later) of the environment forming device 3 are connected to each other, for example, by an RS-485 cable.

FIG3 is a diagram schematically showing the structure of the environment forming device 3. In the example of the present embodiment, the environment forming device 3 uses a HALT (Highly Accelerated Limit Test) test device, a HASS (High Accelerated Stress Screen) test device, or a HASA (High Accelerated Stress Audit) test device. The inspection object of the HALT test device is mainly a test product. The HALT test device must confirm the weak points of the test product with respect to the environment and continuously applies environmental stress until the inspection object fails (until the defective part is detected). The inspection objects of the HASS test device and the HASA test device are mainly actual products. The HASS test is a full inspection of all actual products, and the HASA test is a sampling inspection of a part of the actual products. HALT test equipment, HASS test equipment, or HASA test equipment is to apply vibration stress and/or temperature stress that exceeds the assumed range (specification range) of the actual product usage to the inspection object, thereby realizing high acceleration testing. Vibration stress is applied by vibration in the extension direction and rotation direction of each axis of the three orthogonal axes (X-axis and Y-axis in the horizontal plane and Z-axis in the vertical direction), and 6 degrees of freedom vibration stress can be applied. However, as long as the vibration stress that will be generated in the actual product usage or exceeds the assumed range of 3 degrees of freedom of the actual product usage can be applied, it will be fine. The vibration stress of 6 degrees of freedom (3 degrees of freedom or more) is different from the vibration of one axis or two axes. It is a complex vibration that will be generated in the actual use of the product, or exceeds the assumed range of the use of the actual product. The reliability of the inspection object can be evaluated in a shorter time by the vibration stress of 6 degrees of freedom (3 degrees of freedom or more). The vibration acceleration can be set arbitrarily in the range of 5~75 (Grms). The temperature stress is a temperature stress that can be applied in a wide temperature range (e.g. -100~+200℃) and rapidly changing (e.g. average 70℃/min).

As shown in FIG3 , the environment forming device 3 includes an air-conditioning chamber 23 and a cavity 24 surrounded by an insulating frame 25. The air-conditioning chamber 23 is provided with a blower 26 for air circulation, a heater 27 for heating, and a nozzle 28 for spraying liquid nitrogen for cooling. The nozzle 28 is connected to a tank 31 of liquid nitrogen disposed outside the environment forming device 3 through a pipe 29. The pipe 29 is provided with a valve 30 for controlling whether liquid nitrogen can be supplied from the tank 31 to the nozzle 28. The conditioned air generated in the air-conditioning chamber 23 is supplied from the air-conditioning chamber 23 to the cavity 24 through the air supply port 42 as shown by the arrow A. After circulating in the cavity 24, the conditioned air is discharged from the cavity 24 to the air-conditioning chamber 23 through the exhaust port 41.

A flat plate-shaped vibration table 32 is arranged in the cavity 24. The vibration table 32 is supported by a support member 34 fixed to the side of the frame 25 through a spring 33 so that it can swing. The vibration table 32 is driven by an actuator 35, thereby realizing the above-mentioned 6-degree-of-freedom vibration. The actuator 35 is constructed using a plurality of (for example, 5) air cylinders with different movement directions. The compressed air is repeatedly supplied and exhausted to each air cylinder in a short cycle, thereby realizing vibration movement in each air cylinder.

On the upper surface of the vibration table 32 in the cavity 24, the circuit substrate 100 as the inspection object is fixed by the fixing member 38. Although omitted in the figure, in the circuit substrate 100, semiconductor devices such as FPGA (Field Programmable Gate Array) applicable to JTAG (Joint Test Action Group) are assembled on the printed circuit board by soft soldering or the like using connection methods such as BGA (Ball Grid Array). The circuit substrate 100 is connected with the wire 40 used for the communication boundary scan test data (test data and test result data, etc.). The wire 40 is pulled out to the outside of the frame 25 through the wire hole 39 formed on the side wall of the frame 25 to be connected to the relay unit 17 shown in Figure 2. The circuit board 100 housed by the environment forming device 3 and the test controller 13 of the inspection device 2A are connected to each other through the wire 40 and the relay unit 17.

Furthermore, the environment forming device 3 includes an environment controller 22, a communication unit 21, a temperature detector 37, and a vibration detector 36. The temperature detector 37 is disposed in the cavity 24. The vibration detector 36 is constructed using an acceleration detector, etc., and is disposed on the vibration table 32.

The environmental controller 22 is composed of a processor such as a CPU and a memory such as a ROM and a RAM. The environmental controller 22 controls the driving of the heater 27, the valve 30 and the actuator 35 respectively by various control signals. The application of temperature stress and vibration stress to the circuit substrate 100 is controlled by the environmental controller 22.

The environment controller 22 is input with temperature data indicating the temperature in the cavity 24 detected by the temperature detector 37. The environment controller 22 controls the heater 27 and the valve 30 based on the temperature data input from the temperature detector 37, and can control the temperature in the cavity 24 to the target value. In addition, the environment controller 22 is input with vibration data indicating the vibration acceleration of the vibration table 32 detected by the vibration detector 36. The environment controller 22 controls the actuator 35 based on the vibration data input from the vibration detector 36, thereby controlling the vibration acceleration of the vibration table 32 to the target value.

Furthermore, these temperature data and vibration data are input from the environment controller 22 to the cavity monitor 12 (see FIG. 2 ) through the communication unit 21, 16. Thus, the state (temperature and vibration) of the cavity 24 of the environment forming device 3 can be monitored by the cavity monitor 12 of the inspection device 2A.

FIG4 is a graph showing the first example of the vibration stress application mode for the circuit substrate 100. The horizontal axis of the curve graph represents the elapsed time, and the vertical axis represents the magnitude of the vibration acceleration. In the first example, the environment controller 22 keeps the vibration acceleration of the vibration table 32 at a constant value during the entire period from the start of the test to the end of the test. Thus, a constant vibration stress is applied to the circuit substrate 100 during the entire period from the start of the test to the end of the test.

FIG5 is a diagram showing the second example of the vibration stress application mode for the circuit substrate 100. In the second example, the environmental controller 22 causes the period of vibrating the vibration table 32 (setting the vibration acceleration to a predetermined value, thereby the vibration becomes "ON") and the period of not vibrating the vibration table 32 (setting the vibration acceleration to zero, thereby the vibration becomes "OFF") to repeat alternately. Thus, the period of applying vibration stress to the circuit substrate 100 (ON period) and the period of not applying vibration stress (OFF period) are repeated alternately. Moreover, the length of the ON period and the length of the OFF period can be the same or different. In addition, during the ON period, the vibration acceleration can be a constant value or a variable value.

FIG6 is a diagram showing the third example of the vibration stress application pattern for the circuit board 100. In the third example, the environment controller 22 causes the vibration table 32 to vibrate more (the vibration acceleration is set to a value greater than a certain reference value, thereby making the vibration a "large" period) and the vibration table 32 to vibrate less (the vibration acceleration is set to a value less than the reference value, thereby making the vibration a "small" period) to repeat alternately. Thus, the period (large period) in which a larger vibration stress is applied to the circuit board 100 and the period (small period) in which a smaller vibration stress is applied are repeated alternately. Moreover, the length of the large period and the length of the small period can be the same or different. Furthermore, in the long period and the short period, the vibration acceleration can be a constant value or a variable value.

FIG. 7 is a diagram showing the fourth example of the vibration stress application mode for the circuit substrate 100. In the fourth example, the environment controller 22 changes the vibration acceleration in a step-like manner to a gradually larger value as time passes. Thus, the vibration stress that increases in a step-like manner gradually over time is applied to the circuit substrate 100. Moreover, contrary to the example shown in FIG. 7, the vibration stress that decreases in a step-like manner gradually over time can be applied to the circuit substrate 100. Moreover, the increase or decrease amplitude of the vibration acceleration that changes in a step-like manner can be a constant value or a variable value. Moreover, the mode of increasing the vibration stress in a step-like manner and the mode of decreasing the vibration stress in a step-like manner can be combined.

FIG8 is a diagram showing the fifth example of the vibration stress application mode for the circuit substrate 100. In the fifth example, the environment controller 22 linearly changes the vibration acceleration to a gradually larger value as time passes. Thus, the vibration stress that increases linearly and gradually as time passes is applied to the circuit substrate 100. In addition, contrary to the example shown in FIG8, the vibration stress that decreases linearly and gradually as time passes can be applied to the circuit substrate 100. In addition, the mode of linearly increasing the vibration stress and the mode of linearly decreasing the vibration stress can be combined.

The environmental controller 22 can execute all the vibration stress application modes shown in Figures 4 to 8 for the circuit substrate 100, or execute only one. In addition, the environmental controller 22 can also execute any combination of the vibration stress application modes shown in Figures 4 to 8 for the circuit substrate 100. For example, it can also execute

． After the first example (Figure 4), execute the second example (Figure 5).

． Mix the ON period and OFF period of the second example (Figure 5) with the large period and small period of the third example (Figure 6).

．In the middle of the 4th example (Figure 7) or the 5th example (Figure 8), insert the OFF period of the 2nd example (Figure 5) or the short period of the 3rd example (Figure 6).

In addition, the environmental controller 22 can also apply temperature stress to the circuit board 100 in addition to the vibration stress. The information indicating whether a certain application mode must be executed corresponds to the type of the circuit board 100, etc., and is set in advance in the environmental controller 22.

In the inspection device 2A of the present embodiment shown in FIG. 2 , the system controller 11 causes the test controller 13 to perform a boundary scan test on the circuit substrate 100 while the environment forming device 3 applies the above-mentioned vibration stress (and temperature stress) to the circuit substrate 100. In addition, in the following description, although an example is given in which the system controller 11 determines the execution timing of the boundary scan test, the present invention is not limited to this example. The same function as that of the system controller 11 may also be assembled in the test controller 13, whereby the test controller 13 determines the execution timing of the boundary scan test. In this case, the test controller 13 includes the function of playing a test control unit that controls the boundary scan test, and the function of playing a main control unit that allows the test control unit to execute the boundary scan test and determines the execution timing of the boundary scan test. In addition, in the following description, although the example in which the inspection device 2A includes the system controller 11 and the test controller 13 separately is described, the present invention is not limited to this example. The inspection device 2A may also include a controller having the functions of the system controller 11 and the test controller 13. In this case, the one controller includes the function of playing a test control unit as described above, and the function of playing a main control unit as described above.

FIG9 is a graph showing the first example of the execution timing of the boundary scan test for the circuit substrate 100. The horizontal axis of the curve graph represents the elapsed time, and the vertical axis represents the magnitude of the vibration acceleration. In addition, the arrow P represents the timing of executing the boundary scan test. The application mode of the vibration stress adopts the example shown in FIG5. The test controller 13 performs multiple boundary scan tests on the circuit substrate 100. In the first example shown in FIG9, the execution interval of the boundary scan test is an interval W0 regardless of whether the vibration stress is in the ON period or the OFF period, which is constant (called "constant mode").

FIG10 is a diagram showing a second example of the execution timing of the boundary scan test on the circuit substrate 100. The vibration stress application mode adopts the example shown in FIG5. The test controller 13 performs a plurality of boundary scan tests on the circuit substrate 100. In the second example shown in FIG10, the system controller 11 makes the execution interval of the boundary scan test different according to the application condition of the vibration stress. Specifically, the system controller 11 sets the execution interval of the boundary scan test to a relatively wide interval W11 during the OFF period (e.g., time T0~T1) when the magnitude of the vibration stress is less than the first predetermined value. Furthermore, the system controller 11 sets the execution interval of the boundary scan test to interval W12 which is narrower than interval W11 (referred to as "variation mode corresponding to the magnitude of vibration stress") during the ON period (e.g., time T3-T4) when the magnitude of vibration stress is greater than the first predetermined value.

According to this example, when the magnitude of the vibration stress is greater than the first predetermined value, it is easier to produce defects. Therefore, the system controller 11 sets the execution interval of the boundary scan test to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the magnitude of the vibration stress is less than the first predetermined value, it is more difficult to produce defects. Therefore, the system controller 11 sets the execution interval of the boundary scan test to be longer, thereby avoiding an increase in the amount of data in the test results.

Another example is that the system controller 11 can also make the execution interval of the boundary scan test different according to the application time of the vibration stress. Specifically, the system controller 11 measures the application time of the vibration stress to the circuit substrate 100 after the test starts. When the application time of the vibration stress is less than the second predetermined value, the execution interval of the boundary scan test is set to a wider interval W11. In addition, when the application time of the vibration stress is greater than the second predetermined value, the system controller 11 sets the execution interval of the boundary scan test to an interval W12 that is narrower than the interval W11 (referred to as "variation mode corresponding to the application time of the vibration stress").

According to this example, when the application time of the vibration stress is greater than the second predetermined value, it is easier to produce defects, so the system controller 11 sets the execution interval of the boundary scan test to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the application time of the vibration stress is less than the second predetermined value, it is more difficult to produce defects, and the system controller 11 sets the execution interval of the boundary scan test to be longer, thereby avoiding an increase in the amount of data in the test results.

Furthermore, contrary to the above, in the case where defects are more likely to occur, the execution interval of the boundary scan test is set to be longer, and in the case where defects are less likely to occur, the execution interval of the boundary scan test is set to be shorter. This can reliably detect defects in the circuit board 100, making it possible to detect defects at an early stage.

FIG. 11 is a diagram showing the third example of the execution timing of the boundary scan test for the circuit substrate 100. The vibration stress application mode adopts the example shown in FIG. 7. The system controller 11 makes the execution interval of the boundary scan test different according to the application conditions of the vibration stress. Specifically, the system controller 11 sets the execution interval of the boundary scan test to a relatively wide interval W21 in the OFF period (time T0~T1) when the vibration stress is not applied. In addition, the system controller 11 sets the execution interval of the boundary scan test to an interval W22 that is narrower than the interval W21 in the next period (time T1~T2) after the vibration stress increases by one step. Furthermore, the system controller 11 sets the execution interval of the boundary scan test to interval W23 which is narrower than interval W22 in the next period (time T2-T3) when the magnitude of the vibration stress further increases by one level. In this way, the system controller 11 sets the execution interval of the boundary scan test to be gradually narrowed each time the magnitude of the vibration stress increases by one level.

According to this example, the greater the vibration stress, the easier it is to produce defects, so the system controller 11 sets the execution interval of the boundary scan test to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, the smaller the vibration stress, the harder it is to produce defects, so the system controller 11 sets the execution interval of the boundary scan test to be longer, thereby avoiding an increase in the amount of data in the test results.

Furthermore, contrary to the above, in the case where defects are easy to occur, the execution interval of the boundary scan test can be set to be longer, and in the case where defects are difficult to occur, the execution interval of the boundary scan test can be set to be shorter. In this case, it is possible to detect defects in the circuit substrate 100 accurately, so that the occurrence of defects can be discovered at an early stage.

FIG. 12 is a diagram showing the fourth example of the execution timing of the boundary scan test for the circuit substrate 100. The application mode of the vibration stress adopts the example shown in FIG. 7. In addition to the vibration stress, the temperature stress is applied. The magnitude of the vibration stress is increased by one level in conjunction with a cycle of the temperature cycle (e.g., time T3 to T5). The system controller 11 makes the execution interval of the boundary scan test different according to the application condition of the temperature stress. Specifically, the system controller 11 sets the execution interval of the boundary scan test to a relatively wide interval W31 during the period when the magnitude of the temperature stress has not transitioned, that is, during the period when the temperature is approximately constant (including completely constant situations and situations where the fluctuation range is less than the predetermined value and changes slightly) (temperature maintenance period). In addition, the system controller 11 sets the execution interval of the boundary scan test to an interval W32 narrower than the interval W31 during the period when the magnitude of the temperature stress transitions (temperature transition period) (referred to as "variation mode corresponding to the applied condition of the temperature stress").

According to this example, it is easier to produce defects during the transition period of the temperature stress, so the system controller 11 sets the execution interval of the boundary scan test to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, it is more difficult to produce defects during the period when the temperature stress is constant, so the system controller 11 sets the execution interval of the boundary scan test to be longer, thereby avoiding the increase of the data volume of the test results.

Furthermore, contrary to the above, the execution interval of the boundary scan test during the temperature maintenance period can be set shorter than the execution interval of the boundary scan test during the temperature transition period. In this case, even during the temperature maintenance period where defects are less likely to occur, defects in the circuit substrate 100 can be detected reliably, making it possible to detect the occurrence of defects at an early stage.

Alternatively, the system controller 11 may set the execution interval of the boundary scan test to a relatively wide interval W31 during a period when the magnitude of the vibration stress is constant, and set the execution interval of the boundary scan test to an interval W32 that is narrower than the interval W31 during a period when the magnitude of the vibration stress is transitioning. In this case, it is easier to produce a defect during a period when the magnitude of the vibration stress is transitioning, so the system controller 11 sets the execution interval of the boundary scan test to a shorter interval, thereby enabling early detection of a defect in the circuit board 100.

For another example, the system controller 11 can also make the execution interval of the boundary scan test different in response to the detection of the defective location by the boundary scan test. Specifically, the system controller 11 counts the number of defective locations detected by the boundary scan test based on the test result data received from the environment forming device 3. When the count value of the number of defective locations (the accumulated value since the start of the test) is less than the third predetermined value, the system controller 11 sets the execution interval of the boundary scan test to a wider interval W31. Furthermore, when the count value of the number of defective locations is greater than the third predetermined value, the system controller 11 sets the execution interval of the boundary scan test to interval W32 which is narrower than interval W31 (referred to as "variable mode corresponding to the detection of defective locations").

According to this example, when the number of defective locations detected by the boundary scan test is greater than the third predetermined value, it is easier to generate other defects, so the system controller 11 sets the execution interval of the boundary scan test to be shorter, thereby detecting other defects at an early stage. In addition, when the number of defective locations detected by the boundary scan test is less than the third predetermined value, it is harder to generate defects, so the system controller 11 sets the execution interval of the boundary scan test to be longer, thereby avoiding an increase in the amount of data in the test results.

Furthermore, contrary to the above, the execution interval of the boundary scan test when the number of detected defective locations is less than the third predetermined value can be set shorter than the execution interval of the boundary scan test when the number of detected defective locations is greater than the third predetermined value. In this case, even in a situation where it is difficult for a defect to occur, it is possible to reliably detect that a defect has occurred in the circuit substrate 100, thereby enabling the occurrence of a defect to be discovered at an early stage.

Furthermore, when the vibration stress application mode adopts the example shown in FIG. 4, the system controller 11 can adopt any one of a fixed mode, a variable mode corresponding to the vibration stress application time, a variable mode corresponding to the detection condition of the defective location, and a variable mode corresponding to the application condition of the temperature stress for the execution interval of the boundary scan test.

Furthermore, when the vibration stress application mode adopts the example shown in Figures 5 to 8, the system controller 11 can adopt any one of the following modes for the execution interval of the boundary scan test: a fixed mode, a variable mode corresponding to the magnitude of the vibration stress, a variable mode corresponding to the application time of the vibration stress, a variable mode corresponding to the detection of the defective location, and a variable mode corresponding to the application condition of the temperature stress.

The system controller 11 determines that the circuit board 100 has a fault when the number of defective detections (or the defective detection ratio) within a predetermined unit period by the boundary scanning test exceeds a predetermined threshold value. Even when the circuit board 100 has a soft solder joint defect such as a crack, when the degree of the defect is small, the crack may be an accidental contact failure during the detection time and may not be detected. After the degree of the defect is determined by applying vibration stress, even if the detection time overlaps with the OFF period, it is very likely that the crack is not in contact with the ground and is detected as a defect. Therefore, the fault determination is performed based on the number of defective detections (or the defective detection ratio) within a predetermined unit period, thereby detecting whether the degree of the defect has been completed.

<Conclusion>

When the inspection device 2 according to this embodiment is used, the circuit substrate 100 to be inspected is received by the environment forming device 3, and the system controller 11 (main control unit) causes the test controller 13 (test control unit) to perform a boundary scanning test on the circuit substrate 100 while the environment forming device 3 applies a vibration stress of more than 3 degrees of freedom to the circuit substrate 100. In this way, the boundary scanning test is performed on the circuit substrate 100 while applying a vibration stress of more than 3 degrees of freedom exceeding the assumed range of the use of the actual product, thereby promoting the occurrence of defects in the circuit substrate 100 and evaluating the generated defective location with high accuracy. As a result, the time required for testing can be shortened while improving the reliability of actual products.

Furthermore, the environment forming device 3 uses a HALT test device, a HASS test device, or a HASA test device, thereby applying a 6-degree-of-freedom vibration stress and a wide temperature range and rapidly changing temperature stress to the circuit substrate 100. As a result, it becomes possible to effectively promote the occurrence of defects in the circuit substrate 100.

<Variation example>

FIG. 13 is a block diagram schematically showing the structure of the inspection device 2 (2B) of the modification. A scanner unit 18 is added to the structure shown in FIG. 2. In this modification, the environment forming device 3 accommodates a plurality of circuit substrates 100 (100_1 to 100_N) of the same type. The plurality of circuit substrates 100_1 to 100_N are connected in parallel to the relay unit 17. Each circuit substrate 100 and the relay unit 17 are connected to each other by a set of five wires for connecting each port such as TDI (test data input), TCK (test clock), TMS (test mode selection), TRST (test reset), and TDO (test data output). The mark "(N)" in FIG. 13 means summarizing N sets of parallel wiring between the circuit substrates 100_1~100_N and the relay unit 17. The scanner unit 18 switches the connection between the test controller 13 and the plurality of circuit substrates 100_1~100_N, so that one of the circuit substrates 100 in the plurality of circuit substrates 100_1~100_N is connected to the test controller 13.

The system controller 11 allows the scanner unit 18 to repeatedly execute the connection process of sequentially connecting a circuit substrate 100 to the test controller 13 when the environment forming device 3 applies environmental stress to the multiple circuit substrates 100_1~100_N. In addition, the system controller 11 is linked with the connection process to allow the test controller 13 to perform a boundary scan test on a circuit substrate 100, thereby performing multiple boundary scan tests on each of the multiple circuit substrates 100_1~100_N. Here, the so-called "linkage" means that the switching of the connection made by the scanner unit 18 and the execution of the boundary scan test made by the test controller 13 are synchronized with each other.

FIG. 14 is a diagram schematically showing the structure of the scanner unit 18. The scanner unit 18 has a plurality of circuit substrates 100_1~100_N as the inspection object, and a plurality of channels C (C1~CN) of the same number (or more). Each channel C includes a normally open contact switch S (S1~SN). One terminal of each switch S is connected to the test controller 13, and the other terminal is connected to the circuit substrate 100_1~100_N through the relay unit 17.

By the switching control of the system controller 11, one switch S among the switches S1 to SN is closed, thereby, a circuit substrate 100 connected to the switch S is connected to the test controller 13. That is, the switching control of the switches S1 to SN is equivalent to the selection control of the channels C1 to CN, and by closing a switch S, a corresponding channel C is selected. In FIG. 14, the switch S1 is closed and the channel C1 is selected, thereby indicating that the circuit substrate 100_1 is connected to the test controller 13. In addition, it is also possible to replace all of the five ports that can be switched by the switch S1, and adopt a structure in which only a desired port among the five ports can be switched by the switch S1. It is also possible to use a structure where only two ports, TDI (test data input) and TDO (test data output), can be switched by switch S1.

In this variation, the test controller 13 performs a plurality of boundary scan tests for each of the plurality of circuit substrates 100_1 to 100_N. The system controller 11 makes the execution intervals of the boundary scan tests for the remaining circuit substrates 100 different in accordance with the detection of the defective locations by the boundary scan test for one circuit substrate 100. Specifically, when the number of defective locations detected by the boundary scan test for each circuit substrate 100 is less than the fourth predetermined value, the system controller 11 sets the execution interval of the boundary scan test for all circuit substrates 100 to the first interval, which is relatively wide. Furthermore, when the number of defective locations detected by the boundary scanning test for at least one circuit substrate 100 is greater than the fourth predetermined value, the system controller 11 sets the execution interval of the boundary scanning test for all circuit substrates 100 to a second interval narrower than the first interval.

According to this variation, the scanner unit 18 (connection switching unit) repeatedly performs connection processing for sequentially connecting a circuit substrate 100 to the test controller 13, and the test controller 13 is linked to the connection processing to perform a boundary scanning test on a circuit substrate 100. In this way, a test controller 13 is used to continuously perform a boundary scanning test on each of the plurality of circuit substrates 100_1~100_N, so that the boundary scanning test on the plurality of circuit substrates 100_1~100_N can be efficiently performed. As a result, the test cost can be reduced.

Furthermore, when according to the present variation, when the number of defective locations detected by the boundary scanning test on at least one circuit substrate is greater than the fourth predetermined value, defects are more likely to occur in other circuit substrates 100. Therefore, the system controller 11 sets the execution interval of the boundary scanning test on all circuit substrates 100 to be shorter, thereby enabling early detection of the occurrence of defects. In addition, when the number of defective locations detected by the boundary scanning test for each circuit substrate 100 is less than the fourth predetermined value, it is difficult for all circuit substrates 100 to produce defects. Therefore, the system controller 11 sets the execution interval of the boundary scanning test for all circuit substrates 100 to be longer, thereby avoiding an increase in the amount of test result data.

Moreover, in this variant, a circuit structure in which a semiconductor device is assembled on a circuit substrate 100 is taken as a premise, but the present invention is not limited to this example. It is also possible that a circuit substrate 100 is assembled with multiple semiconductor devices. In this case, one channel C is allocated relative to one semiconductor device, whereby the selection of channel C becomes equivalent to the switching of the semiconductor device.

An inspection device according to one aspect of the present invention is an inspection device that can be communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and is characterized in that it includes: a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit; the main control unit allows the test control unit to perform the boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate.

According to this aspect, the circuit substrate to be inspected is accommodated by the environment forming device, and the main control unit allows the test control unit to perform a boundary scan test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate. In this way, the boundary scan test is performed on the circuit substrate when a vibration stress of more than 3 degrees of freedom that may occur in the use of the actual product or that exceeds the assumed range of the use of the actual product is applied to the circuit substrate. This can promote the occurrence of defects in the circuit substrate and can evaluate the location of the defect with high accuracy. As a result, the time required for the test can be shortened while improving the reliability of the actual product.

In the above embodiment, the test control unit performs the boundary scan test multiple times on the circuit substrate, and the main control unit makes the execution interval of the boundary scan test different according to the application condition of the vibration stress.

According to this state, the main control unit makes the execution interval of the boundary scanning test different according to the conditions for applying vibration stress. Therefore, when the conditions for applying vibration stress are conditions that are more likely to cause defects, the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the conditions for applying vibration stress are conditions that are more difficult to cause defects, the main control unit sets the execution interval to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above embodiment, when the magnitude of the vibration stress is greater than the first predetermined value, the main control unit makes the execution interval of the boundary scanning test narrower compared with the case where the magnitude of the vibration stress is less than the first predetermined value.

According to this state, when the magnitude of the vibration stress is above the first predetermined value, it is easier to produce a defect, so the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of a defect at an early stage. In addition, when the magnitude of the vibration stress is less than the first predetermined value, it is harder to produce a defect, so the main control unit sets the execution interval to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above embodiment, when the application time of the vibration stress is greater than the second predetermined value, the main control unit makes the execution interval of the boundary scanning test narrower compared with the case where the application time of the vibration stress is less than the second predetermined value.

According to this state, when the vibration stress application time is greater than the second predetermined value, it is easier to produce defects, so the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the vibration stress application time is less than the second predetermined value, it is more difficult to produce defects, so the main control unit sets the execution interval to be longer, thereby avoiding the increase of the data volume of the test results.

In the above embodiment, the test control unit performs the boundary scan test multiple times on the circuit substrate, and the main control unit makes the execution interval of the boundary scan test different according to the detection of the defective location made by the boundary scan test.

According to this situation, the main control unit makes the execution interval of the boundary scan test different according to the detection of the defective locations made by the boundary scan test. Therefore, when more than a certain number of defective locations are detected, which is a situation where other defects are more likely to occur, the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of other defects at an early stage. In addition, when more than a certain number of defective locations are not detected, which is a situation where defects are more difficult to occur, the main control unit sets the execution interval to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above aspect, when the number of defective locations detected by the boundary scan test is greater than the third predetermined value, the main control unit makes the execution interval of the boundary scan test narrower than the case where the number of defective locations detected by the boundary scan test is less than the third predetermined value.

According to this situation, when the number of defective locations detected by the boundary scanning test is greater than the third predetermined value, it is a situation where other defects are more likely to occur, so the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of other defects at an early stage. In addition, when the number of defective locations detected by the boundary scanning test is less than the third predetermined value, it is a situation where it is more difficult to produce defects, so the main control unit sets the execution interval to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above aspect, the at least one circuit substrate includes a first circuit substrate and a second circuit substrate, the test control unit performs the boundary scanning test multiple times for each of the first circuit substrate and the second circuit substrate, and the main control unit makes the execution interval of the boundary scanning test for the second circuit substrate different in response to the detection of the defective location by the boundary scanning test for the first circuit substrate.

According to this state, the main control unit makes the execution interval of the boundary scanning test for the second circuit substrate different in accordance with the detection of the defective parts by the boundary scanning test for the first circuit substrate. Therefore, when a certain number of defective parts are detected in the first circuit substrate and the defective parts are more likely to occur in the second circuit substrate, the main control unit sets the execution interval for the second circuit substrate to be shorter, thereby detecting the occurrence of the defective parts at an early stage. In addition, when more than a certain number of defective locations in the first circuit substrate are not detected and it is also difficult for defects to occur in the second circuit substrate, the main control unit sets the execution interval for the second circuit substrate to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above aspect, when the number of defective locations detected by the boundary scanning test on the first circuit substrate is greater than the fourth predetermined value, the main control unit makes the execution interval of the boundary scanning test on the second circuit substrate narrower than the case where the number of defective locations detected by the boundary scanning test on the first circuit substrate is less than the fourth predetermined value.

According to this state, when the number of defective locations detected by the boundary scanning test on the first circuit substrate is greater than the fourth predetermined value, it is also more likely that defects will occur in the second circuit substrate, so the main control unit sets the execution interval for the second circuit substrate to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the number of defective locations detected by the boundary scanning test on the first circuit substrate is less than the fourth predetermined value, it is also more difficult that defects will occur in the second circuit substrate, so the main control unit sets the execution interval for the second circuit substrate to be longer, thereby avoiding an increase in the amount of test result data.

In the above-mentioned aspect, the environment forming device can also apply temperature stress to the circuit substrate, the test control unit performs the boundary scanning test multiple times on the circuit substrate, and the main control unit makes the execution interval of the boundary scanning test different according to the application conditions of the temperature stress.

According to this state, the main control unit makes the execution interval of the boundary scanning test different according to the application conditions of the temperature stress. Therefore, when the application conditions of the temperature stress are conditions that are more likely to produce defects, the main control unit sets the execution interval to be shorter, thereby detecting the occurrence of defects at an early stage. In addition, when the application conditions of the temperature stress are conditions that are less likely to produce defects, the main control unit sets the execution interval to be longer, thereby avoiding an increase in the amount of data in the test results.

In the above aspect, the main control unit makes the execution interval of the boundary scanning test narrower during the period when the magnitude of the temperature stress is in transition compared to the period when the magnitude of the temperature stress is not in transition.

According to this situation, when the temperature stress is in transition, it is easier to produce defects, so the main control unit sets the execution interval to be shorter, so that the occurrence of defects can be discovered early. In addition, when the temperature stress is not in transition, it is more difficult to produce defects, so the main control unit sets the execution interval to be longer, so as to avoid the increase of the data volume of the test results.

In the above aspect, the at least one circuit substrate is a plurality of circuit substrates, and the test control unit performs the boundary scanning test on each of the plurality of circuit substrates. It also includes a connection switching unit that can switch the connection between the test control unit and the plurality of circuit substrates accommodated by the environment forming device, so that one of the plurality of circuit substrates is connected to the test control unit. The main control unit allows the connection switching unit to repeatedly execute the connection processing of sequentially connecting the one circuit substrate to the test control unit when the environment forming device applies the vibration stress to the plurality of circuit substrates, and is linked to the connection processing to allow the test control unit to perform the boundary scanning test on the one circuit substrate.

According to this aspect, the connection switching unit repeatedly executes the connection processing of sequentially connecting a circuit substrate to the test control unit, and the test control unit is linked to the connection processing to perform a boundary scan test on a circuit substrate. In this way, a boundary scan test for each of a plurality of circuit substrates is continuously performed using a test control unit, so the boundary scan test for a plurality of circuit substrates can be efficiently performed. As a result, the test cost can be reduced.

In the above embodiment, the environment forming device is a HALT test device, a HASS test device, or a HASA test device.

When the environment forming device is based on this state, the HALT test device, HASS test device, or HASA test device is used, thereby applying 6 degrees of freedom vibration stress and wide temperature range and rapidly changing temperature stress to the circuit substrate. As a result, it becomes possible to effectively promote the occurrence of defects in the circuit substrate.

An inspection system of one aspect of the present invention includes: an environment forming device that can accommodate at least one circuit substrate as an inspection object; and an inspection device that can be communicatively connected to the environment forming device; the inspection device has: a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit; the main control unit allows the test control unit to perform the boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate.

According to this aspect, the circuit substrate to be inspected is accommodated by the environment forming device, and the main control unit allows the test control unit to perform a boundary scan test on the circuit substrate while the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate. In this way, the boundary scan test is performed on the circuit substrate while applying a vibration stress of more than 3 degrees of freedom that will be generated in the actual product usage or that exceeds the assumed range of the actual product usage. This can promote the generation of defects in the circuit substrate and can evaluate the generated defective location with high accuracy. As a result, the time required for the test can be shortened while improving the reliability of the actual product.

The inspection method of one aspect of the present invention includes: applying a vibration stress of more than 3 degrees of freedom to at least one circuit substrate accommodated by an environment forming device by means of the environment forming device; and performing a boundary scanning test on the circuit substrate while the environment forming device applies the vibration stress to the circuit substrate.

According to this aspect, the circuit substrate to be inspected is accommodated in the environment forming device, and the environment forming device performs a boundary scanning test on the circuit substrate under a state where a vibration stress of more than 3 degrees of freedom is applied to the circuit substrate. In this way, a boundary scanning test is performed on the circuit substrate under a state where a vibration stress of more than 3 degrees of freedom that would be generated in the actual product usage or that exceeds the assumed range of the actual product usage is applied to the circuit substrate, thereby promoting the generation of defects in the circuit substrate and evaluating the generated defective location with high accuracy. As a result, the time required for the test can be shortened while improving the reliability of the actual product.

2A: Inspection device

11: System controller

12: Cavity monitor

13: Test the controller

14: Memory Department

15: Display unit

16: Communications Department

17: Relay unit

21: Communications Department

40: Wires

100: Circuit board

Claims (15)

An inspection device is communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and includes a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit that allows the test control unit to execute the boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate; the test control unit executes the boundary scanning test on the circuit substrate multiple times; the main control unit is configured to determine the execution interval of the boundary scanning test, corresponding to the application condition of the vibration stress, so that the execution interval of the boundary scanning test is different. As in the inspection device of claim 1, the main control unit makes the execution interval of the boundary scanning test narrower when the magnitude of the vibration stress is greater than the first predetermined value, compared with the case where the magnitude of the vibration stress is less than the first predetermined value. As in the inspection device of claim 1, the main control unit makes the execution interval of the boundary scanning test narrower when the application time of the vibration stress is greater than the second predetermined value compared with the case where the application time of the vibration stress is less than the second predetermined value. An inspection device is communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and includes a test control unit that controls a boundary scan test on the circuit substrate; and a main control unit that allows the test control unit to perform the boundary scan test on the circuit substrate when the environment forming device applies a vibration stress of more than 3 degrees of freedom to the circuit substrate; The test control unit performs the boundary scan test on the circuit substrate multiple times, and the main control unit is configured to determine the execution interval of the boundary scan test, corresponding to the detection of a defective location by the boundary scan test, so that the execution interval of the boundary scan test is different. As in the inspection device of claim 4, the main control unit makes the execution interval of the boundary scan test narrower when the number of defective locations detected by the boundary scan test is greater than the third predetermined value, compared with the case where the number of defective locations detected by the boundary scan test is less than the third predetermined value. An inspection device is communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and includes a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit that allows the test control unit to execute the boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than three degrees of freedom to the circuit substrate; wherein the at least one circuit substrate is The circuit board includes a first circuit board and a second circuit board. The test control unit performs the boundary scanning test multiple times for each of the first circuit board and the second circuit board. The main control unit is configured to determine the execution interval of the boundary scanning test, and to make the execution interval of the boundary scanning test for the second circuit board different in accordance with the detection of the defective location by the boundary scanning test for the first circuit board. The inspection device of claim 6, wherein the main control unit makes the execution interval of the boundary scanning test for the second circuit substrate narrower when the number of defective locations detected by the boundary scanning test for the first circuit substrate is greater than the fourth predetermined value, compared with the case where the number of defective locations detected by the boundary scanning test for the first circuit substrate is less than the fourth predetermined value. An inspection device is communicatively connected to an environment forming device that can accommodate at least one circuit substrate as an inspection object, and includes a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit that allows the test control unit to execute a boundary scanning test on the circuit substrate when the environment forming device applies a vibration stress of more than three degrees of freedom to the circuit substrate. The boundary scanning test on the circuit substrate; wherein the environment forming device can also apply temperature stress to the circuit substrate, the test control unit performs the boundary scanning test multiple times on the circuit substrate, and the main control unit is configured to determine the execution interval of the boundary scanning test, corresponding to the application condition of the temperature stress, so that the execution interval of the boundary scanning test is different. The inspection device of claim 8, wherein the main control unit makes the execution interval of the boundary scanning test narrower when the magnitude of the temperature stress is in the transition period compared to when the magnitude of the temperature stress is not in the transition period. The inspection device of any one of claims 1 to 9, wherein the at least one circuit substrate is a plurality of circuit substrates, the test control unit performs the boundary scanning test on each of the plurality of circuit substrates, and further includes a connection switching unit that can switch the connection between the test control unit and the plurality of circuit substrates accommodated by the environment forming device, so that one of the plurality of circuit substrates is connected to the test control unit, and the main control unit is to allow the connection switching unit to repeatedly perform the connection processing of sequentially connecting the one circuit substrate to the test control unit when the environment forming device applies the vibration stress to the plurality of circuit substrates, and to link the connection processing to allow the test control unit to perform the boundary scanning test on the one circuit substrate. The inspection device of any one of claim items 1 to 9, wherein the environment forming device is a HALT (Highly Accelerated Limit Test) test device, a HASS (High Accelerated Stress Screen) test device, or a HASA (High Accelerated Stress Audit) test device. An inspection system includes: an environment forming device that can accommodate at least one circuit substrate as an inspection object; and an inspection device that is communicatively connected to the environment forming device, the inspection device having: a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit that applies a test condition to the circuit substrate when the environment forming device is in operation. Under the state of vibration stress with more than 3 degrees of freedom, the test control unit performs the boundary scan test multiple times on the circuit substrate; the main control unit is configured to determine the execution interval of the boundary scan test, corresponding to the application conditions of the vibration stress or the detection of the defective location by the boundary scan test, so that the execution interval of the boundary scan test is different. An inspection system includes: an environment forming device that can accommodate at least one circuit substrate as an inspection object; and an inspection device that can be connected to the environment forming device in a communicative manner, and the inspection device has: a test control unit that controls a boundary scanning test on the circuit substrate; and a main control unit that applies 3 In the state of vibration stress with more than 100 degrees of freedom, the test control unit performs the boundary scanning test multiple times on the circuit substrate; wherein the environment forming device can also apply temperature stress to the circuit substrate, and the main control unit is configured to determine the execution interval of the boundary scanning test, and the execution interval of the boundary scanning test is different corresponding to the application condition of the temperature stress. An inspection method includes: applying a vibration stress of more than 3 degrees of freedom to at least one circuit substrate accommodated by an environment forming device; and performing a boundary scanning test on the circuit substrate multiple times at intervals determined and different according to the conditions for applying the vibration stress or the detection of a defective location by the boundary scanning test, while the environment forming device applies the vibration stress to the circuit substrate. A testing method, comprising: applying vibration stress and temperature stress of more than 3 degrees of freedom to at least one circuit substrate accommodated by an environment forming device; and performing the boundary scanning test on the circuit substrate multiple times at intervals determined and different from the application conditions of the temperature stress while the environment forming device applies the vibration stress and the temperature stress to the circuit substrate.

Images