METHOD FOR MEASURING CURRENT, METHOD FOR INSPECTING SEMICONDUCTOR DEVICE, SEMICONDUCTOR DEVICE, AND TEST ELEMENT GROUP

• US 20110148455A1
• Filed: 12/14/2010
• Published: 06/23/2011
• Est. Priority Date: 12/18/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Sekine, Yusuke, Shionoiri, Yutaka, Kato, Kiyoshi
• Granted Patent: US 9,057,758 B2
• Time in Patent Office: Days
• US Class Current: 324/762.01
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 31/275 for testing individual semiconductor components within integrated circuits
• CPC Class Codes: G01R 31/2884 using dedicated test connectors, test elements or test circuits on the IC under test G01R31/2855 takes precedence
• CPC Class Codes: G09G 2320/029 by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters

Abstract

An object is to provide a current measurement method which enables a minute current to be measured. To achieve this, the value of a current flowing through an electrical element is not directly measured, but is calculated from a change in potential observed in a predetermined period. The detection of a minute current can be achieved by a measurement method including the steps of applying a predetermined potential to a first terminal of an electrical element comprising the first terminal and a second terminal; measuring an amount of change in potential of a node connected to the second terminal; and calculating, from the amount of change in potential, a value of a current flowing between the first terminal and the second terminal of the electrical element.

Claims

1. A method for measuring current, comprising the steps of:

applying a predetermined potential to a first terminal of an electrical element comprising the first terminal and a second terminal;

measuring an amount of change in potential of a node connected to the second terminal; and

calculating, from the amount of change in potential, a value of a current flowing between the first terminal and the second terminal of the electrical element.

2. The method for measuring current according to claim 1,

wherein the electrical element is a transistor in which a current flowing between a source and a drain when the transistor is in an off state is less than 10⁻

14 A,

wherein the first terminal is one of the source and the drain,

wherein the second terminal is the other of the source and the drain, and

wherein by forcing the transistor into the off state, a value of a current flowing when the transistor is in the off state is calculated.

3. The method for measuring current according to claim 1, wherein a capacitor is connected to the node.

4. A method for inspecting a semiconductor device, comprising the step of:

inspecting where or not the electrical element has predetermined characteristics by using the method for measuring current according to claim 1.

5. A semiconductor device employing the method for inspecting the semiconductor device according to claim 4.

6. A semiconductor device comprising the electrical element having a parameter which is determined on the basis of the value of the current determined by the method for measuring current according to claim 1.

7. A method for measuring current, comprising the steps of:

applying a predetermined potential to a first terminal of an electrical element comprising the first terminal and a second terminal;

supplying charge to a node connected to the second terminal;

measuring an amount of change in potential of the node due to a change in an amount of charge held in a capacitor connected to the node; and

calculating, from the amount of change in potential, a value of a current flowing between the first terminal and the second terminal of the electrical element.

8. The method for measuring current according to claim 7,

wherein the electrical element is a transistor in which a current flowing between a source and a drain when the transistor is in an off state is less than 10⁻

14 A,

wherein the first terminal is one of the source and the drain,

wherein the second terminal is the other of the source and the drain, and

wherein by forcing the transistor into the off state, a value of a current flowing when the transistor is in the off state is calculated.

9. A method for inspecting a semiconductor device, comprising the step of:

inspecting where or not the electrical element has predetermined characteristics by using the method for measuring current according to claim 7.

10. A semiconductor device employing the method for inspecting the semiconductor device according to claim 9.

11. A semiconductor device comprising the electrical element having a parameter which is determined on the basis of the value of the current determined by the method for measuring current according to claim 7.

12. A test element group comprising:

an electrical element comprising a first terminal and a second terminal;

a capacitor; and

an output circuit comprising an input terminal and an output terminal,

wherein the first terminal of the electrical element is a terminal to which a potential from a power source is applied, and

wherein the second terminal of the electrical element is connected to a first terminal of the capacitor and the input terminal of the output circuit.

13. The test element group according to claim 12, wherein the potential is applied to the first terminal in order to calculate, from an amount of change in a potential of the output terminal of the output circuit, a value of a current flowing between the first terminal and the second terminal of the electrical element.

14. The test element group according to claim 12,

wherein the electrical element is a transistor in which a current flowing between a source and a drain when the transistor is in an off state is less than 10⁻

14 A,

wherein the first terminal is one of the source and the drain, and

wherein the second terminal is the other of the source and the drain.