Method for measuring spreading resistance and spreading resistance microscope

Patent metadata

Field	Value
Publication number	US-9823208-B2
Application number	US-201615084976-A
Country	US
Kind code	B2
Filing date	Mar 30, 2016
Priority date	Mar 30, 2015
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A method includes: removing at least a part of an oxide formed on a surface of the sample by relatively scanning the surface of the sample in X and Y directions parallel to the surface while bringing a probe into contact with the surface of the sample; detecting a signal by bringing the probe into contact with the surface of the sample from which at least a part of the oxide is removed at a predetermined detection position in the X direction or the Y direction while a bias voltage is applied to the sample; calculating a spreading resistance value based on the signal; and retracting the probe to keep the probe relatively away from the surface in a Z direction perpendicular to the surface while relatively moving the probe to a next detection position to start scanning the sample from the next detection position.

First claim

What is claimed is:

1. A method for measuring spreading resistance of a sample, the method comprising:
removing at least a part of an oxide formed on a surface of the sample by relatively scanning the surface of the sample in X and Y directions parallel to the surface while bringing a probe into contact with the surface of the sample;
detecting a signal by bringing the probe into contact with the surface of the sample from which at least a part of the oxide is removed at a predetermined detection position in the X direction or the Y direction while a bias voltage is applied to the sample;
calculating a spreading resistance value based on the signal; and
retracting the probe to keep the probe relatively away from the surface in a Z direction perpendicular to the surface while relatively moving the probe to a next detection position to start scanning the sample from the next detection position.

2. The method according to claim 1 ,
wherein, in detecting the signal, the probe is fixed at the predetermined detection position in the X and Y directions.

3. The method according to claim 1 ,
wherein, in detecting the signal, light irradiation for detecting a position of the probe in the Z direction is stopped.

4. A spreading resistance microscope comprising:
a probe that has an electrical conductivity;
a controller configured to control relative movement of the probe in X and Y directions parallel to a surface of a sample and relative movement of the probe in a Z direction perpendicular to the surface of the sample;
a bias voltage applying unit comprising a bias power supply and configured to apply a bias voltage to the sample;
a detector configured to detect a signal generated from the probe when the probe is brought into contact with the surface of the sample and the bias voltage is applied to the sample; and
a spreading resistance value calculator configured to calculate a spreading resistance value based on the detected signal,
wherein the controller operates to perform a process including:
removing at least a part of an oxide formed on the surface of the sample by relatively scanning the surface of the sample in X and Y directions parallel to the surface of the sample while bringing a probe into contact with the surface of the sample;
controlling the detector to detect the signal by bringing the probe into contact with the surface of the sample from which at least a part of the oxide is removed at a predetermined detection position in the X direction or the Y direction while the bias voltage is applied to the sample; and
retracting the probe to keep the probe relatively away from the surface of the sample in a Z direction perpendicular to the surface of the sample while relatively moving the probe to a next detection position to start scanning the sample from the next detection position.

5. The spreading resistance microscope according to claim 4 ,
wherein the controller controls the probe to be fixed at the predetermined detection position in the X and Y directions.

6. The spreading resistance microscope according to claim 4 ,
wherein the controller stops light irradiation for detecting a position of the probe in the Z direction when detecting the signal.

Assignees

• Hitachi High-Tech Science Corp

Inventors

• Watanabe Masafumi
• Yamaoka Takehiro

Classifications

• G01Q60/30 Primary

  Scanning potential microscopy · CPC title

• G01N17/00

  Investigating resistance of materials to the weather, to corrosion, or to light · CPC title

• G01N27/041 Primary

  of a solid body · CPC title

• G01L1/20

  by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids (of piezo-resistive materials G01L1/18); by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress · CPC title

• G01L1/22

  using resistance strain gauges · CPC title