JP2000046885A - Apparatus for testing static electricity breakdown endurance amount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To test a static electricity breakdown endurance amount by reproducing a failure mechanism possibly brought about in the present situation not only for a single electronic component, but for objects of a large or complicate shape such as a product with the parts mounted. SOLUTION: A charging means is placed above an object 1 to be measured which is loaded on an object stage 1. An induction charge is induced to the object 11 on the object stage 1 via the charging means. An endurance amount when an internal circuit of the object 11 to be measured breaks down because of the induction charge is measured. The charging means consists of a charging plate 10 arranged opposite to the object 11 to be measured in a noncontact fashion and a corona generator having a corona discharge electrode 8 disposed opposite to the charging plate 10 for charging the charging plate 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic breakdown withstand test apparatus capable of determining the electrostatic breakdown strength of an electronic component in a state where the electronic component is mounted on a substrate as well as an electronic component alone. The present invention relates to an electrostatic discharge withstand test apparatus for measuring a withstand voltage at which an internal circuit is destroyed by an electric charge induced by an electric field.

[0002]

2. Description of the Related Art Conventionally, as this kind of electrostatic breakdown resistance test apparatus, there is one disclosed in, for example, Japanese Patent Application Laid-Open No. 6-58985. As shown in FIG. An apparatus for performing an electrostatic breakdown resistance test of a component has been proposed. This device employs a method using an object mounting table 1 for applying a voltage to the ground and a discharge electrode 3 for discharging electric charges from an external lead terminal 4 of the electronic component 2 to the ground.

[0003] In addition to the above conventional example, as shown in FIG. There is also a method in which discharge between the two is prevented.

[0004] When the electrostatic breakdown resistance test is performed by this method, first, a voltage is applied to the object mounting table 1, and charges generated by electrostatic induction are transferred from the external lead terminals 4 to the ground side via the discharge electrodes 3. Then, by checking the electrical characteristics of the internal circuit of the electronic component 2, the presence or absence of destruction is measured, and the breakdown resistance is measured.

[0005]

However, according to the above-mentioned conventional system, the electronic component 2 is mounted on the object mounting table 1 to which a voltage is applied with respect to the ground. Since there is a possibility that the space between the object mounting table 1 and the external lead terminals 4 becomes narrow or comes into contact with each other, a discharge may occur when a high voltage is applied.

In addition, the object mounting table 1 is prevented from discharging between the external lead terminals 4 and the object mounting table 1.
In the method of interposing the insulating plate 5 between the electronic component 2 and
Since the object mounting table 1 is charged to a high voltage, the insulation of the insulating plate 5 itself is destroyed, which involves considerable danger.

In addition, in the above-described conventional method, there are restrictions on the parts that can be tested, and the shape of a mounted product is large.
In addition, it is difficult to perform measurement when the circuit components are complicated.

[0008] Further, a failure mechanism which is usually assumed is that a failure is caused by electrostatically charging by an electrostatic induction by an electric field generated from a charged insulator, for example, a packaging material, and releasing the charge, thereby causing a failure. The scheme is different from the actual possible failure mechanism.

The object of the invention according to the present application is not limited to a single electronic component, but it is also possible to reproduce a failure mechanism that can occur at present, even for a large or complicated one such as a mounted product thereof, by electrostatic discharge. An object of the present invention is to provide an electrostatic breakdown withstand test apparatus capable of performing a breakdown withstand test.

[0010]

As a first configuration for realizing the object of the invention according to the present application, a measuring object mounting table for charging a measuring object to be mounted, and a measuring object mounting table, A discharge electrode for discharging electric charges from a terminal of the object to be measured on the mounting table, and inspecting electrical characteristics after the discharge of the object to be measured by the discharge electrode to detect an electrostatic breakdown withstand. In the proof test apparatus, a charging unit is arranged above the measurement target placed on the measurement target mounting table, and guided to the measurement target on the measurement target mounting table via the charging unit. The electric charge is induced.

According to the above-described structure, the object to be measured is not directly charged by the metal plate to which a voltage is applied with respect to the ground as in the prior art, but is arranged in a non-contact manner with the object to be measured. By generating an induced charge, a large shape like a mounted product other than a single electronic component,
In addition, it is possible to easily measure the electrostatic breakdown strength of a complicated circuit configuration that is destroyed by electrostatic discharge. In addition, since there is no possibility that the space between the mounting table and the object to be measured becomes narrow or there is no risk of contact, the discharge does not occur when a high voltage is applied.

As a second configuration for realizing the object of the invention according to the present application, the charging means comprises: a charging plate which is arranged in non-contact with the object to be measured; and a corona discharge electrode which is close to the charging plate. And a corona generator that charges the charging plate via the charging device. According to the above-described configuration, it is not necessary to charge the object-to-be-measured mounting table to a high voltage, so that a test can be performed in which a failure mechanism that can normally occur is reproduced.

As a third configuration for realizing the object of the invention according to the present application, the charging means includes a static eliminator for neutralizing a charge previously charged on the charging plate. According to the above-described configuration, it is possible to easily return to the state before the test simply by neutralizing the electric charge preliminarily charged on the charging plate by the static eliminator, and to quickly perform the next test.

As a fourth structure for realizing the object of the invention according to the present application, the charging means has a surface voltmeter for measuring the surface potential of the charging plate.

According to the above configuration, a desired charging potential can be controlled while measuring the surface potential of the charging plate with the surface voltmeter.

According to a fifth configuration for realizing the object of the present invention, the charging plate has a surface resistivity of 1 × 10 ¹⁴ Ω.
It is characterized by the above.

According to the above configuration, it is possible to minimize the leakage of the charged electric charge of the charging plate.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a block diagram showing the outline of an electrostatic discharge withstand test apparatus according to a first embodiment of the present invention.

Reference numeral 1 denotes a conductive object mounting table, for example, made of metal or the like, on which an object 11 to be measured such as an electronic component or a component mounted thereon is mounted, and is always grounded. Reference numeral 5 denotes an object mounting table 1 and an object 1
1 is an insulating plate installed between the mounting table 1
It prevents discharge between the object and the object to be measured 11.

Reference numeral 3 denotes a discharge electrode for discharging electric charges from the measured object 11 side to the ground side.

Reference numeral 10 denotes a charging plate for generating an induced charge in a conductor portion of the object 11 to be measured by electrostatic induction in the vicinity of the object 11 to be measured.
In order to prevent the charged charges from leaking, for example, the surface resistivity is set to about 1 × 10 ¹⁴ Ω or more.

Reference numeral 9 denotes a direct-current corona generator for generating a local discharge through the needle-shaped corona discharge electrode 8 brought close to the measured object 11 to charge the charging plate 10 to a desired potential. And connected to either the anode side or the cathode side of the two power supplies via a switch so as to be capable of being reverse-biased so as to generate a positive corona or a cathode corona. .

Reference numeral 6 denotes a static eliminator for neutralizing the electric charge previously charged on the charging plate 10 before the test.

Reference numeral 7 denotes a surface voltmeter for measuring the potential on the surface of the charging plate 10.
While controlling the surface potential of 0, it can be controlled so as to be a desired charging potential.

Next, an example of use of this embodiment will be described. As shown in FIG. 1, after neutralizing a pre-charged charge using a static eliminator 6, an object 11 to be measured is placed on an insulating plate 5 on a grounded object mounting table 1. .

Next, the charging plate 10 is
To a desired potential. At this time, the surface of the charging plate 10 is controlled so as to have a desired charging potential while measuring the potential with the surface voltmeter 7.

When the charging plate 10 is charged to a desired potential, the corona generator 9 is stopped, and electric charges are discharged from the terminal at which the object 11 to be measured is to be measured using the discharge electrode 3.

After the charge is released, the object to be measured 11
By measuring the electrical characteristics of the device and examining the presence or absence of destruction, the resistance to electrostatic breakdown is measured.

[0029]

According to the first aspect of the present invention, the object to be measured is not directly charged by the metal plate to which a voltage is applied with respect to the ground as in the prior art, but is not contacted with the object to be measured. By generating induced charge by the placed charging plate, it is easy to measure the electrostatic discharge withstand capacity that can be destroyed by electrostatic discharge even for a large and complicated circuit configuration such as a mounted product other than a single electronic component. can do. In addition, since there is no possibility that the space between the mounting table and the object to be measured becomes narrow or there is no risk of contact, the discharge does not occur when a high voltage is applied.

According to the second aspect of the present invention, it is not necessary to charge the object mounting table to a high voltage, so that a test that reproduces a failure mechanism that can occur normally can be performed.

According to the third aspect of the present invention, only by neutralizing the charge pre-charged on the charging plate by the static eliminator,
It can be easily returned to the state before the test, and the next test can be quickly performed.

According to the fourth aspect of the present invention, it is possible to control a desired charging potential while measuring the surface potential of the charging plate with the surface voltmeter.

According to the fifth aspect of the present invention, it is possible to minimize the leakage of the charged electric charge of the charging plate.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a test apparatus according to a first embodiment of the present invention;

FIG. 2 is a configuration diagram showing an outline of a test apparatus in a conventional example.

FIG. 3 is a configuration diagram schematically showing another test apparatus in a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Mounted object to be measured 2 ... Electronic parts 3 ... Discharge electrode 4 ... External lead terminal 5 ... Insulating plate 6 ... Static eliminator 7 ... Surface potential meter 8 ... Corona discharge electrode 9 ... DC power supply 10 ... Charging plate 11 ... Object to be measured (electronic components and their mounted products)

Claims (5)

[Claims] An object mounting table for charging an object to be mounted, and a discharge electrode for discharging electric charges from a terminal of the object on the object mounting table, In an electrostatic discharge immunity test apparatus for detecting electrical breakdown strength by examining electrical characteristics after discharge of the measurement object by the discharge electrode, the measurement object mounted on the measurement object mounting table A charging means is disposed above the device, and induced charge is induced on the object to be measured on the object mounting table via the charging means. 2. The image forming apparatus according to claim 1, wherein the charging unit includes a charging plate disposed to face the object to be measured in a non-contact manner, and a corona generator configured to charge the charging plate via a corona discharge electrode close to the charging plate. The electrostatic breakdown resistance test apparatus according to claim 1, wherein: 3. The electrostatic breakdown withstanding test apparatus according to claim 2, wherein said charging means includes a static eliminator for neutralizing a charge previously charged on the charging plate. 4. The apparatus according to claim 2, wherein said charging means has a surface voltmeter for measuring a surface potential of said charging plate. 5. The charging plate has a surface resistivity of 1 × 10 ¹⁴ Ω.
The electrostatic breakdown withstand test apparatus according to any one of claims 2 to 4, wherein: