JPH0320681A - Method of inspecting leak current of semiconductor device - Google Patents

Abstract

PURPOSE:To enable stable inspection by a method wherein the ground terminal of an IC is grounded to the ground part of a tester, and a small negative potential not causing PN junction is applied to a leak current inspection terminal to inspect a leak current. CONSTITUTION:A ground part 6 of a tester is made to earth a ground terminal 2 of an IC 1 to be inspected and a leak current inspection terminal 3 is con nected to a voltage power source 5 of the tester. A fine negative potential allowed to conduct noa PN junction is applied to the voltage source 5 and the current flowing through the voltage source 5 is measured with an ammeter 4 to judge the IC to be acceptable. This enables inspection equivalently in elec tricity while stable inspection of leak current is accomplished even against effect of mechanical noises of a handle and power source ripple.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a leakage current testing method used in testing static characteristics of semiconductor devices.

BACKGROUND OF THE INVENTION In recent years, semiconductor devices (hereinafter referred to as ICs) have become increasingly flat packaged, and there are also cases in which they are shipped with comb frames attached at the request of users.

A conventional leakage current testing method will be explained below.

FIG. 2 shows a conventional leak testing method. Second
In the figure, 1 is the IC to be tested, 2 is the ground terminal of the IC, and 3
4 is a leak current test terminal, 4 is an ammeter, 5 is a voltage source, and 6 is a grounding portion of the tester.

FIG. 3 shows the state of automatic inspection. In FIG. 3, 1 is the IC to be tested, 12 is the Au wire 13 is the substrate, 14 is the adhesive, 8 is the comb frame, 9 is the separation layer, 7 is the ground terminal pad of the IC, 2 is the ground terminal of the IC, 3
10 is a leak current test terminal, 10 is an automatic handler, 11 is a tester, 4 is an ammeter, 5 is a voltage source, and 6 is a grounding part of the tester.

The operation of the leakage current testing method configured as described above will be explained below.

First, the ground terminal of the IC to be tested is connected to a voltage source, and then the leak current test terminal is connected to the ground portion of the tester. Then, a minute positive potential that does not cause the PN junction to conduct is applied to the voltage source, and the current flowing through the voltage source is measured with an ammeter to determine whether the product is good or defective.

Problems to be Solved by the Invention However, with the above-mentioned precautions, a problem arises when leakage current is inspected with the comb frame attached.

The explanation will be given below. The ground terminal of the IC is A. It is electrically connected to the comb frame through the U wire, ground terminal pad, separation layer, substrate, and adhesive. When inspecting ICs, automatic inspection is performed using a handler, but since the guide rail of the handler and the comb frame are in contact, mechanical noise and power ripples from the handler may affect the grounding of the IC through the comb frame. affect When testing using the conventional leakage current testing method, the IC's grounding terminal is not grounded, so the IC's grounding has the disadvantage of becoming unstable due to the effects of mechanical noise and power supply ripples. was.

The present invention solves the above-mentioned problems, and aims to stabilize leakage current inspection of ICs in all conditions.

Means for Solving the Problems In order to achieve this object, the leakage current testing method of the present invention connects the grounding terminal of the IC to the grounding part of the tester, connects a voltage source to the leakage current testing terminal, and connects the PN junction to the grounding terminal of the IC. It has a configuration in which a minute negative potential that does not conduct is applied and the current flowing through the voltage source is inspected.

Function: This configuration in which the ground terminal of the IC is grounded to the ground portion of the tester allows noise and power ripple generated from the handler to be absorbed by the ground portion of the tester before they affect the IC. This makes it possible to stably test leakage current.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows a leakage current testing method according to an embodiment of the present invention.

In Figure 1, 1 is the IC to be tested, 2 is the ground terminal of the IC,
3 is a leak current test terminal, 4 is a current pin, 15 is a voltage source,
6 is the grounding part of the tester.

The operation of the current testing method constructed as described above will be described below.

First, the ground terminal of the IC to be tested is grounded to the ground portion of the tester. Also, connect the terminal to be tested for leakage current to the voltage source of the tester. Then, a minute negative potential that does not cause the PN junction to conduct is applied to the voltage source, and the current flowing through the voltage source is read with an ammeter to determine whether the product is good or defective.

As described above, by providing the leakage current testing method according to this embodiment, it is possible to conduct a test that is electrically equivalent to the conventional leakage current testing method, and is also resistant to the effects of mechanical noise of the handler and power supply ripples. Leak current inspection can be performed stably.

Effects of the Invention As described above, the present invention provides an effective method for testing IC leakage current.
This method is electrically equivalent to the conventional leakage current testing method by grounding the grounding terminal of the tester to the grounding part of the tester and applying a minute negative potential that does not cause PN junction conduction to the terminal to be tested for leakage current. This is an excellent leakage current testing method that can perform accurate testing, and can stably test leakage currents even against the effects of mechanical noise and power supply ripples.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing the leakage current testing method in the embodiment, Fig. 2 is a circuit diagram showing the conventional leakage current testing method, and Fig. 3 is a circuit diagram showing the state of conventional automatic testing. It is. 1... IC to be tested, 2... IC grounding terminal, 3... Leak current inspection terminal, 4...
... Ammeter, 5 ... Voltage source, 6 ... Grounding part of the tester.

Claims (1)

[Claims] A semiconductor device characterized by connecting the grounding terminal of the semiconductor device and the grounding terminal of the tester in automatic testing of the static characteristics of the semiconductor device, and applying a minute negative potential to the leakage current testing terminal to the extent that the PN junction does not conduct. Method for testing equipment leakage current.