JP3251210B2 - Semiconductor integrated circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor integrated circuit device, and more particularly to a semiconductor integrated circuit device capable of quickly performing a failure analysis when a defective product or a defect occurs.

[0002]

2. Description of the Related Art Conventionally, there is a semiconductor integrated circuit disclosed in Japanese Patent Application Laid-Open No. 2-58862 as a semiconductor integrated circuit device capable of confirming the basic characteristics of a device without impairing the original function of a product.

This semiconductor integrated circuit includes an integrated circuit having a function as a product therein and a basic transistor (basic element). A first terminal newly added among terminals having several to several tens of pins is provided. The first to third terminals include an external terminal, and two transmission gates are configured as a second terminal and two transmission gates are configured as a third terminal in order to switch between the integrated circuit and the basic transistor. The control is performed by the first terminal.

In this semiconductor integrated circuit, switching is performed by changing one of the two transmission gates of the second and third terminals by changing the voltage level of the first terminal. ,
It is possible to measure the electrical characteristics of a single element from which the basic characteristics of the device can be obtained.

[0005]

A problem with the above-described semiconductor integrated circuit is that since no bias is applied to the basic element for measuring the electric characteristics, an abnormality is found in the electric characteristics of the basic element during failure analysis. When it is detected, it cannot be determined whether it is an abnormality already created during the manufacturing process or an original operation of the product, and sufficient data cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is a semiconductor capable of measuring a change in electric characteristics of a basic element representing an electric characteristic of an integrated circuit main body due to bias application. An object of the present invention is to provide an integrated circuit device.

[0007]

In order to solve the above-mentioned problems, the present invention employs the following semiconductor integrated circuit device.
That is, in the semiconductor integrated circuit device according to the first aspect, the semiconductor chip can directly measure the integrated circuit main body, the basic element representing the electric characteristic of the integrated circuit main body, and the electric characteristic of the basic element from the outside. A plurality of external terminals, wherein a plurality of switching elements capable of applying a bias voltage to the basic element from the integrated circuit main body are provided between the basic element and the integrated circuit main body. Things.

According to a second aspect of the present invention, there is provided a semiconductor integrated circuit device having a plurality of external terminals connected to the integrated circuit main body for directly operating the switching element from the outside.

According to a third aspect of the present invention, in the semiconductor integrated circuit device, the switching element includes a transistor.

In the semiconductor integrated circuit device according to the first or third aspect of the present invention, between the basic element representing the electrical characteristics of the integrated circuit main body and the integrated circuit main body, the integrated circuit main body is connected to the basic element. By providing a plurality of switching elements to which a bias voltage can be applied, by turning on / off these switching elements, the bias voltage is turned on / off to the basic element.

Therefore, the variation in the electrical characteristics of the basic element caused by the application of the bias voltage can be accurately measured by comparing the fluctuation with the basic element before or after the change or before the bias voltage is applied. become. Further, by turning on / off the switching element, it is possible to apply the same bias voltage as that of the integrated circuit body to the basic element except when measuring the electrical characteristics.

In the semiconductor integrated circuit device according to the second aspect,
By providing the integrated circuit body with a plurality of external terminals for directly operating the switching element from the outside, it becomes possible to measure the electrical characteristics of the basic element even after packaging.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the semiconductor device of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a semiconductor integrated circuit device according to an embodiment of the present invention. In the drawing, reference numeral 1 denotes a semiconductor chip, 2 denotes an internal element of the integrated circuit (integrated circuit main body), and 3 denotes an electric characteristic measurement. 4 is a plurality of bias applying switches (switching elements) for applying a bias voltage from the internal element 2 of the integrated circuit to the basic element 3, and 5 is a plurality of external switches for directly measuring the electrical characteristics of the basic element 3 from outside. Terminals 6 are a plurality of external terminals connected to the internal element 2 of the integrated circuit for directly operating the bias applying switch 4 from outside.

In this semiconductor integrated circuit device, the integrated circuit
External terminal 6 connected to the internal element 2 of the integrated circuit
When a signal for closing the bias application switch 4 is input from the device, and the bias application switch 4 is closed, a bias voltage is applied from the internal element 2 to the basic element 3 of the integrated circuit. It is desirable that the bias voltage can be freely changed according to a voltage level considered necessary for failure analysis.

Here, first, a change in electrical characteristics caused by application of a bias voltage to the basic element 3 is measured. Next, a signal for opening the bias application switch 4 is input from the external terminal 6, and when the bias application switch 4 is opened, no bias voltage is applied from the internal element 2 of the integrated circuit to the basic element 3. Therefore, the electrical characteristics of the basic element 3 in a state where no bias voltage is applied are measured.

Here, the electrical characteristics of the basic element 3 when the bias is applied are compared with those of the basic element 3 to which no bias voltage is applied, so that the electrical characteristics of the basic element 3 can be accurately determined. Can be measured.

FIG. 2 is a circuit diagram showing the basic element 3 of the semiconductor integrated circuit device of the present embodiment. In the figure, reference numeral 11 denotes a three-terminal N-type MOS transistor used as the basic element 3 for measuring electric characteristics. Yes, gate is external terminal 5a
To the external terminal 5b and the source to the external terminal 5c.
Connected to each other.

A transistor 12, which is a bias application switch 4, is provided between the gate and the internal element 2 of the integrated circuit. The gate of the transistor 12 is connected to the external terminal 6a. Similarly, a transistor 13 is provided between the drain and the internal element 2, and the gate of the transistor 13 is connected to the external terminal 6.
b. Similarly, the source and ground 15
The transistor 14 is also provided between the first and second transistors, and the gate of the transistor 14 is connected to the external terminal 6c.

In the N-type MOS transistor 11, signals for turning on / off the transistors 12 to 14 are input from the external terminals 6a to 6c of the transistors 12 to 14, respectively.
Each is turned on / off, and the operation as the bias application switch 4 is performed. For example, when the transistor 12 is turned on, a bias voltage from the internal element 2 is applied to the gate of the N-type MOS transistor 11. This operation is the same for the transistors 13 and 14.

According to the semiconductor integrated circuit device of the present embodiment, the basic element 3 for measuring the electrical characteristics is switched by the transistors 12 to 14 which are the bias application switches 4, so that the basic element 3 A bias voltage can be applied, and a change in electrical characteristics of the basic element 3 due to the application of the bias voltage can be measured.

In the semiconductor integrated circuit device of the present embodiment, the N-type MOS transistor 11 is used as the basic element 3 and the transistors 12 to 14 are used as the bias application switch 4. Any configuration may be used as long as a switching element to which a voltage can be applied is provided, and it is a matter of course that the present invention is not limited to this embodiment.

[0022]

As described above, according to the semiconductor integrated circuit device of the first or third aspect of the present invention, the basic element representing the electric characteristics of the integrated circuit main body and the integrated circuit main body are connected to each other. In between, a plurality of switching elements capable of applying a bias voltage from the integrated circuit body to the basic element are provided. By turning on / off these switching elements, the bias voltage is turned on / off for the basic element. be able to.

Therefore, the variation in the electrical characteristics of the elementary element caused by the application of the bias voltage can be accurately measured by comparing the fluctuation with the elementary element before and after the change or with the element not supplied with the bias voltage. . Further, by turning on / off the switching element, a bias voltage similar to that of the integrated circuit body can be applied to the basic element except when the electrical characteristics are measured.

According to the semiconductor integrated circuit device of the present invention, a plurality of external terminals are provided which are connected to the main body of the integrated circuit and operate the switching element directly from the outside.
Even after packaging, the electrical characteristics of the basic element can be measured.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a semiconductor integrated circuit device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing basic elements of the semiconductor integrated circuit device according to one embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 semiconductor chip 2 internal element of integrated circuit (integrated circuit body) 3 basic element for measuring electric characteristics 4 bias application switch (switching element) 5, 5a, 5b, 5c external terminal 6, 6a, 6b, 6c external terminal 11 N-type MOS transistor 12-14 Transistor 15 Ground

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01R 31/28-31/3193 H01L 21/822 H01L 27/04

Claims (3)

(57) [Claims] A semiconductor chip includes an integrated circuit main body, a basic element representing electric characteristics of the integrated circuit main body, and a plurality of external terminals capable of directly measuring the electric characteristics of the basic element from outside. Semiconductor integrated circuit device, wherein a plurality of switching elements capable of applying a bias voltage from the integrated circuit body to the basic element are provided between the basic element and the integrated circuit body. apparatus. 2. The semiconductor integrated circuit device according to claim 1, further comprising a plurality of external terminals connected to said integrated circuit main body for directly operating said switching element from outside. 3. The switching device according to claim 1, wherein the switching element is configured by a transistor.
13. The semiconductor integrated circuit device according to claim 1.