KR20010044350A - Integrated circuit burn-in test apparatus having connection fail check mode, probing board and method for checking connection fail - Google Patents

Abstract

PURPOSE: An integrated circuit burn-in apparatus having a connection inspecting function is provided to automatically inspect an electrical connection state before inspecting an integrated circuit or while the inspection process is performed. CONSTITUTION: A control unit controls an inspection process and a connection inspecting process of a predetermined semiconductor integrated circuit. A driving unit is connected to the control unit, and generates a driving signal for an inspection process of the integrated circuit and the connection inspecting process by a control signal of the control unit. A line transmits the driving signal, connected to the driving unit. A test board is connected to the line, and has a circuit for performing a test of a characteristic according to the specification of the integrated circuit and a circuit for inspecting whether an electrical connection with the driving unit through the line is normal.

Description

INTEGRATED CIRCUIT BURN-IN TEST APPARATUS HAVING CONNECTION FAIL CHECK MODE, PROBING BOARD AND METHOD FOR CHECKING CONNECTION FAIL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated circuit burn-in device having a connection check function, a connection check method, and a test board, and more particularly, to a burn-in device for inspecting a semiconductor integrated circuit. In case that the electrical connection state through the connecting means or the fixing means such as the line and the connector between the measurement card (probe card) in direct contact with the terminal for performing the inspection of the integrated circuit and the main control unit of the apparatus connected thereto, An integrated circuit burn-in device, a connection checking method and an inspection board having a function of automatically checking the electrical connection state before or during the inspection of the integrated circuit, in order to overcome a problem that is difficult to distinguish from the defect of the integrated circuit. It is to provide.

In general, burn-in inspection is divided into package burn-in (PBI) which is performed after packaging is completed after processing of a semiconductor integrated circuit and wafer burn-in (WBI) which is performed in a wafer state. Traditionally, the PBI method has been used, but the PBI takes a long time, and the recent trend of increasing the number of I / Os in integrated circuits reduces the density of sockets on burn-in boards, increasing the cost of burn-in. There is a problem, the WBI method has been used a lot recently, accordingly, the inspection process is simplified and the laser repair of the defective cell after the inspection is possible to increase the yield (yield).

1 shows a configuration of a general wafer burn-in apparatus. As shown in FIG. 1, the wafer burn-in apparatus is applied to an integrated circuit to be inspected by a control signal of the controller 100 and a control signal of the controller 100 for supplying a control signal required for each step of the inspection process according to a predetermined inspection order. A driving unit 300 for generating an appropriate driving signal to be formed, a line 200 connecting the driving unit 300 from the control unit 100, an inspection substrate 600 having a different configuration according to a specification of an integrated circuit to be inspected, A fixing means 500 for fixing the inspection substrate 600 and performing electrical connection, and a line 400 for electrical connection between the fixing means 500 and the driving part 300, and the configuration of the device. Although not an element, an integrated circuit 700 is shown for inspection. In addition, the inspection substrate 600 generally includes an element connecting portion 650 in contact with the external wiring terminals of the integrated circuit to be inspected.

In such a general burn-in apparatus, if the electrical connection state through the line 400 and the fixing means 500 from the driving unit 300 to the inspection substrate 600 is not assured, the integrated circuit to be inspected may be defective or not. There is a problem in that it is not easy to determine whether or not the defect is not able to achieve a predetermined inspection purpose.

In addition, the inspection board 600 has a different configuration according to the specification of the integrated circuit to be inspected, and thus is configured to be detachable. Therefore, the inspection board 600 is often replaced as the inspection target is changed. If it is not performed, there is a problem that the test results become unreliable at all, and after replacing the test substrate 600, a lot of trial and error are required to secure the reliability of the test results. Of the company's feedback, which can cause serious problems for manufacturers to gain competitiveness, given the recent trends in the semiconductor sector, where product life cycles are becoming shorter.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and in a burn-in apparatus for inspecting a semiconductor integrated circuit, a measurement substrate performing inspection of the integrated circuit by directly contacting an external connection terminal of the integrated circuit. (probe card) and before the inspection of the integrated circuit, in order to overcome the problem of indistinguishable from the defect of the integrated circuit if the electrical connection through the line and the fixing means between the drive portion of the device connected thereto is not appropriate To provide an integrated circuit burn-in apparatus, a connection check method, and an inspection board having a function of automatically checking the electrical connection state on the way.

1 shows a configuration of a general wafer burn-in apparatus.

Fig. 2 shows the configuration of a preferred embodiment of the inspection substrate of the present invention.

Fig. 3 shows a preferred configuration of the connection inspection portion of the inspection substrate in the preferred embodiment of the present invention.

4 shows the operation of the connection inspection section in the embodiment of the constant current measurement mode.

Fig. 5 shows the operation of the connection inspection section in the embodiment of the constant voltage measurement mode.

Fig. 6 shows the operation of the connection inspection unit in the characteristic inspection mode of the integrated circuit which is the actual inspection object in the preferred embodiment of the present invention.

7 shows an example of the determination of the measurement result and the connection error for each terminal in performing the constant current test.

In order to achieve the above object, the semiconductor integrated circuit burn-in apparatus according to an aspect of the present invention comprises a control unit for controlling the inspection process and the connection check process of the predetermined semiconductor integrated circuit; A driving unit connected to the control unit and generating a driving signal for the inspection of the integrated circuit and the connection checking process according to a control signal of the control unit; A line connected to the driving unit and transmitting the driving signal; And a test board connected to the line and including a circuit for performing a test of characteristics according to the specification of the integrated circuit and a circuit for checking whether or not an electrical connection with the driving unit through the line is defective. .

According to another aspect of the present invention, an inspection substrate mounted on a burn-in apparatus for inspecting a semiconductor integrated circuit includes a line connected to a driving unit supplying a driving signal for inspecting the integrated circuit in the burn-in apparatus. An input connection portion for electrically connecting the inspection substrate with the inspection substrate; A connection connected to the input connection portion for inspecting an electrical connection state between the drive portion of the burn-in device and the semiconductor integrated circuit to be inspected by a drive signal according to a predetermined program applied from the drive portion of the burn-in device; Inspection unit; And an element connection unit connected to the connection inspection unit and providing an electrical connection to an external connection terminal on the semiconductor integrated circuit to be inspected.

According to another aspect of the present invention, a method for checking an electrical connection state of a line from a drive unit in a burn-in device for inspection of a semiconductor integrated circuit to a test substrate is provided through the line from the drive unit of the burn-in device. Measuring a voltage or current through the line by supplying a constant current or a constant voltage, the voltage being determined by a resistor disposed on the inspection substrate and electrically connected to the line and having a predetermined resistance value; And a determination step of determining whether the line is normally connected by comparing the voltage or current measured in the measuring step with a voltage or current value previously calculated using the resistance value.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 shows the configuration of a preferred embodiment of the inspection substrate 600 of the present invention. The inspection board 600 of this embodiment is a connector and a line directly connected with the fixing means 500 representing another structure composed of a combination of a mechanical support for mounting the inspection board and a connector for providing electrical connection. And an input connection part 620 for performing electrical connection and mechanical connection, and connected to the input connection part 620 to check the electrical connection state of the device from the driving part 300 of the device to the inspection substrate 600. Connection inspection unit 640 for connection, and inspection circuit unit 660 and actual inspection connected to the connection inspection unit for performing a main inspection on whether the integrated circuit is normally operated by varying the configuration according to the specification of the integrated circuit to be inspected. It is comprised by the element connection part 650 for making it connect directly to the terminal of the integrated circuit 700 of object.

In FIG. 3, in the preferred embodiment of the present invention, the preferred configuration of the connection inspection unit 640 of the inspection substrate 600 is shown. The connection test unit 640 may include one or more terminal selection switches (S-1-1 through Sn-1), one or more test switches (S-2-1 through Sn-2), a reference potential switch (Vss), and one or more terminals. Resistors (R1 to Rn) and one or more connection terminals (P1 to Pn).

The terminal selection switch, the test switch, and the reference potential switch may be implemented as a general switching device having an input terminal, an output terminal, and a control terminal, and may be implemented as a relay or a transistor.

The line 400 and the fixing means 500 that extend from the driver 300 to the inspection substrate 600 are made of electrical wiring and a connector for connection. Such wiring can be made according to the user's needs or in the design or arrangement of the device. According to the connection of the wiring of several stages, there may be a variety of parts that can cause a connection error, but in general, the inspection substrate 600 and the fixing means that is often detached according to the specification of the integrated circuit to be inspected ( The connection error between the 500 may occur most frequently. In this embodiment, the test substrate 600 is connected to the test substrate 600 to check whether an electrical connection state from the driver 300 to the test substrate 600 is appropriate. It is one of the main features to include the connection inspection unit 640.

The present embodiment provides an integrated circuit burn-in apparatus and a check circuit having a function of automatically checking the electrical connection state before or during the inspection of the integrated circuit 700 to be inspected. Hereinafter, the operation of the present embodiment will be described in detail. Describe.

The inspection process of the integrated circuit programmed in advance by the control unit 100 of the device is controlled. In order to check the electrical connection state of the device before or during the execution of the program for checking whether the integrated circuit 700 is operating normally, In this case, a separate connection check mode may be executed by a command of the device user. In this case, a series of commands generated from the device controller 100 are transmitted to the driver 300 through the line 200, and the driver 300 is provided. Generates a switch drive signal, terminal input current and voltage for the connection check.

When the connection error occurs due to the poor electrical connection state, there may be a case of opening and shorting of the line. Hereinafter, a constant current measuring mode and a shorting of the line for measuring whether the line is opened or not. It is described in detail by dividing into a constant voltage measurement mode for measuring whether or not.

4 shows the operation of the connection inspection unit 600 in the above embodiment of the constant current measurement mode. As shown in Fig. 4, a predetermined constant input current is supplied from the drive unit 300 of the apparatus, and a signal for driving the switch is supplied to select a line to be checked.

4 shows a case where line 2 is selected, a control signal is input to the line selection switch S-2-1 attached to the corresponding line, and the switch is turned on, and the reference potential switch S-Vss is also controlled. The signal is input and the switch is turned on. In addition, an input current is supplied from the driver 300 of the apparatus, and if the line is normally connected, the terminal voltage of each line when each line is selected is expressed by the following equation.

5 shows the operation of the connection inspection unit 600 in the above embodiment of the constant voltage measurement mode. As shown in Fig. 5, a predetermined constant input voltage is supplied from the driver 300 of the apparatus, and a signal for driving the switch is supplied to select a line to be checked.

In FIG. 5, the second line is selected. The control signal is input to the line selection switch S-2-1 attached to the corresponding line, and the switch is turned on. The control is also performed to the reference potential switch S-Vss. The signal is input and the switch is turned on. In addition, an input current is supplied from the driver 300 of the apparatus, and if the line is normally connected, the terminal current of each line when each line is selected is expressed by the following equation.

Therefore, the normal connection state of the line can be easily known by using the constant current measurement mode or the constant voltage measurement mode as described above, if the resistance values are known in advance, and it is possible to check whether there is an abnormality for each line separately. The normal connection state is of course transmitted to the user through a separate display device or output means through the control unit.

6 shows the operation of the connection inspection unit 600 in the characteristic inspection mode of the integrated circuit which is the actual inspection target in the preferred embodiment of the present invention. As shown in FIG. 6, in the test mode, the connection test unit 600 is unnecessary and all the terminal selection switches are turned on while the test process is performed so as not to have an unnecessary influence on the circuit characteristic test results. It is preferable to turn on, so that the integrated circuit which is a direct inspection target and the driver 600 are electrically connected to each other. Therefore, at this time, it is preferable to turn off the reference potential switch S-Vss. However, if the resistance value is large enough and the current flowing through the resistance is small enough to be negligible compared to the operating current of the integrated circuit to be inspected, the reference potential switch S-Vss. May be kept on, and may be omitted in some cases.

In addition, a modified embodiment in which all the tracks are checked at the same time without a separate check for each track to obtain a result may be possible. In this case, the line selection switch may be omitted.

In addition, the constant current measurement mode and the constant voltage measurement mode can be performed either or both to check the line connection state, and the terminal voltage required for each terminal for a current or voltage value predetermined according to each resistance value. It is possible to check the connection status of each terminal by comparing the current value with the table in advance and comparing it with the result of constant current measurement and voltage measurement.

In determining whether the connection state for each terminal is appropriate, it is practically preferable to leave a certain tolerance range in the constant current measurement result or the constant voltage measurement result, and the difference in the resistance value is different so as to connect at which terminal. It may be easy to determine whether the problem is a problem.

In addition, if the electrical connection to each terminal of the integrated circuit is not interrupted in the connection check process, the applied voltage and current during the connection check process not only affect the characteristics of the integrated circuit but also overlap with the device characteristics. Since the inspection process cannot be performed normally, it is preferable to cut off the inspection switch and to cut off the electrical connection to the integrated circuit during the connection inspection process. However, this does not leave the inspection switch as above and mechanically separate the inspection substrate from the wafer. There may be many modified embodiments, such as when the connection is checked while the connection is blocked.

7 shows an example of the measurement result and the determination of the connection error for each terminal in performing the constant current test. In the example of Fig. 7, it shows that a connection failure occurs at terminal 7 and terminal 9.

The integrated circuit burn-in apparatus and the connection check circuit having the connection check function according to the present invention can be modified and applied in various forms within the scope of the technical idea of the present invention and are not limited to the above preferred embodiment.

For example, the terminal selection switch, the test switch and the reference potential switch may be modified to further include several stages, and the reference potential switch S-Vss may be omitted as necessary. In this case, there is a problem that the load characteristic according to the specification of the semiconductor to be measured and the resistance characteristic overlap with the measurement result of the integrated circuit to be inspected, but since the part according to the resistive load is a known characteristic, It is apparent that the characteristic according to the test result can be easily extracted by easily removing the characteristic according to the test result, and this case will also be within the scope of the technical idea of the present invention.

In addition, the test substrate may be configured to be integrally formed on the same substrate, the input connection portion, the connection inspection portion, the inspection circuit portion, and the element connection portion, may be configured to detach and detach the inspection circuit portion and the element connection portion in some cases, As the specification of the integrated circuit to be inspected varies, it may be easy to configure in this way. However, it is obvious that whether the test substrate is integrally formed or separated from each other in several parts is not an important factor in determining whether it is outside the scope of the technical idea of the present invention. It will be seen as a mere modification of the invention.

In addition, the embodiments and drawings are merely for the purpose of describing the contents of the invention in detail, and are not intended to limit the scope of the technical idea of the invention, the present invention described above is common knowledge in the technical field to which the present invention belongs As those skilled in the art can have various substitutions, modifications, and changes without departing from the spirit and scope of the present invention, it is not limited to the embodiments and the accompanying drawings. And should be judged to include equality.

By means of the integrated circuit burn-in device having a connection check function, a connection check method and an inspection board according to the present invention, a burn-in device for inspecting a semiconductor integrated circuit is in direct contact with an external connection terminal of the integrated circuit. If the electrical connection state through the fixing means or the connecting means such as the line and the connector between the measurement card (probe card) for performing the inspection of the integrated circuit and the main control unit of the apparatus connected thereto, the defect of the integrated circuit and It is possible to provide an integrated circuit burn-in apparatus and a check circuit having a function of automatically checking the electrical connection state before or during the inspection of the integrated circuit and overcoming the difficulty of distinguishing.

Claims (9)

A control unit which controls an inspection process and a connection inspection process of a predetermined semiconductor integrated circuit; A driving unit connected to the control unit and generating a driving signal for the inspection of the integrated circuit and the connection checking process according to a control signal of the control unit; A line connected to the driving unit and transmitting the driving signal; And A semiconductor integrated circuit including an inspection substrate connected to the line and having a circuit for inspecting characteristics according to the specification of the integrated circuit and a circuit for inspecting whether an electrical connection with the driver through the line is defective. Circuit burn-in device. According to claim 1, The inspection board may include: an input connection portion for electrically connecting the line connected to a drive unit for supplying a driving signal for inspection of the integrated circuit to the inspection board in the burn-in device; A connection connected to the input connection portion for inspecting an electrical connection state between the drive portion of the burn-in device and the semiconductor integrated circuit to be inspected by a drive signal according to a predetermined program applied from the drive portion of the burn-in device; Inspection unit; And And a device connection unit connected to the connection inspection unit and providing an electrical connection to an external connection terminal on the semiconductor integrated circuit to be inspected. The method of claim 2, The connection inspection unit, An input terminal, an output terminal, and a control terminal, wherein the input terminal and the control terminal are respectively connected to a line connected to the driving unit through the input connection unit, and the driving unit when performing a characteristic test according to the specification of the integrated circuit. At least one inspection switch electrically connecting each line of the integrated circuit and each line connected to the driving unit by shorting the input terminal and the output terminal when a control signal of the control terminal is applied to the control terminal; And Respectively connected to the line connected to the driving unit through the input connection unit, and having a predetermined resistance value, when a voltage supplied from the driving unit is applied without a connection error, a current according to the resistance value flows or is supplied from the driving unit. And at least one resistor which generates a voltage according to the resistance value when the applied current is applied without a connection error. The method of claim 3, wherein The connection inspection unit, An input terminal, an output terminal, and a control terminal, wherein the input terminal and the control terminal are connected to a line connected to the driving unit through the input connection unit, and a control signal of the driving unit to check the electrical connection state through a specific line And at least one line selection switch for selectively shorting between the input terminal and the output terminal when selectively applied to the control terminal. An inspection substrate mounted in a burn-in apparatus for inspecting a semiconductor integrated circuit, The burn-in apparatus, comprising: an input connection unit for electrically connecting a line connected to a driving unit supplying a driving signal for inspecting the integrated circuit and the inspection substrate; A connection connected to the input connection portion for inspecting an electrical connection state between the drive portion of the burn-in device and the semiconductor integrated circuit to be inspected by a drive signal according to a predetermined program applied from the drive portion of the burn-in device; Inspection unit; And And an element connection portion connected to the connection inspection portion and providing an electrical connection to an external connection terminal on the semiconductor integrated circuit to be inspected. The method of claim 5, The connection inspection unit, An input terminal, an output terminal, and a control terminal, wherein the input terminal and the control terminal are respectively connected to a line connected to the driving unit through the input connection unit, and the driving unit when performing a characteristic test according to the specification of the integrated circuit. At least one inspection switch electrically connecting each line of the integrated circuit and each line connected to the driving unit by shorting the input terminal and the output terminal when a control signal of the control terminal is applied to the control terminal; And Respectively connected to the line connected to the driving unit through the input connection unit, and having a predetermined resistance value, when a voltage supplied from the driving unit is applied without a connection error, a current according to the resistance value flows or is supplied from the driving unit. A substrate for inspection of a semiconductor integrated circuit burn-in device, comprising one or more resistors that generate a voltage according to the resistance value when the applied current is applied without a connection error. The method of claim 6, The connection inspection unit, An input terminal, an output terminal, and a control terminal, wherein the input terminal and the control terminal are connected to a line connected to the driving unit through the input connection unit, and a control signal of the driving unit to check the electrical connection state through a specific line And at least one line selection switch for selectively shorting between the input terminal and the output terminal when selectively applied to the control terminal. In the method of checking the electrical connection state of the line from the drive unit in the burn-in device for inspection of the semiconductor integrated circuit to the inspection substrate, Supplying a constant current or a constant voltage through the line from the drive unit of the burn-in device, the voltage through the line determined by a resistor disposed on the inspection substrate and electrically connected to the line and having a predetermined resistance value Or a measuring step of measuring a current; And And determining whether or not the line is normally connected by comparing the voltage or current measured in the measuring step with a voltage or current value previously calculated using the resistance value. The method of claim 8, Prior to the measuring step, the method further comprises the step of electrically disconnecting the integrated circuit from the driver so as not to affect the characteristics of the integrated circuit during the connection check.