Inspection apparatus and inspection method

Patent metadata

Field	Value
Publication number	US-9759656-B2
Application number	US-201715428372-A
Country	US
Kind code	B2
Filing date	Feb 9, 2017
Priority date	Feb 15, 2016
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

The inspection apparatus includes: a stage that retains the inspection sample; a light irradiator that irradiates the inspection sample with light having a predetermined wavelength to cause the inspection sample to emit a terahertz wave; a detector that detects electric field intensity of the terahertz wave emitted from the inspection sample; and a comparator that compares the electric field intensity of the terahertz wave emitted from the inspection sample to an evaluation reference value. The evaluation reference value is a value (for example, 90% of a saturation value) smaller than an absolute value of the saturation value of the electric field intensity of the terahertz wave, the terahertz wave being generated by irradiating a reference sample, which is a reference of the inspection sample, with the light while different voltages are applied to the reference sample.

First claim

What is claimed is:

1. An inspection apparatus that inspects an insulating film formed on a surface of an inspection sample mainly made of a semiconductor material, the inspection apparatus comprising:
a retainer that retains said inspection sample;
a light irradiator that irradiates said inspection sample with light having a predetermined wavelength to cause said inspection sample to emit a terahertz wave;
a detector that detects electric field intensity of said terahertz wave emitted from said inspection sample; and
a comparator that compares said electric field intensity of said terahertz wave emitted from said inspection sample to an evaluation reference value,
wherein said evaluation reference value is smaller than an absolute value of a saturation value of said electric field intensity of said terahertz wave, said terahertz wave being generated by irradiating a reference sample, which is a reference of the inspection sample, with said light having said predetermined wavelength while different voltages are applied to said reference sample.

2. The inspection apparatus according to claim 1 , further comprising:
a voltage application unit that applies voltage to said inspection sample; and
a voltage changer that changes the voltage applied from said voltage application unit.

3. An inspection apparatus that inspects an insulating film formed on a surface of an inspection sample mainly made of a semiconductor material, the inspection apparatus comprising:
a retainer that retains said inspection sample;
a light irradiator that irradiates said inspection sample with light having a predetermined wavelength to cause said inspection sample to emit a terahertz wave;
a detector that detects electric field intensity of said terahertz wave emitted from said inspection sample;
a voltage application unit that applies voltage to said inspection sample;
a voltage changer that changes the voltage applied from said voltage application unit; and
a voltage specifying unit that specifies an applied voltage at which said electric field intensity of said terahertz wave emitted from said inspection sample becomes zero.

4. The inspection apparatus according to claim 3 , further comprising a converter that converts said electric field intensity of said terahertz wave into electric capacity based on correspondence information between said electric field intensity of said terahertz wave and an electric capacity.

5. The inspection apparatus according to claim 3 , further comprising a net charge deriver that derives a net charge using said applied voltage specified with said voltage specifying unit.

6. The inspection apparatus according to claim 3 , further comprising a scanner that scans said inspection sample with said light having said predetermined wavelength.

7. An inspection method for inspecting an insulating film formed on a surface of an inspection sample mainly made of a semiconductor material, the inspection method comprising steps of:
(a) specifying a saturation value of electric field intensity of a terahertz wave, said terahertz wave being generated by irradiating a reference sample, which is a reference of the inspection sample, with light having a predetermined wavelength while different voltages are applied to said reference sample;
(b) detecting said electric field intensity of said terahertz wave, which is generated by irradiating said inspection sample with said light having said predetermined wavelength; and
(c) comparing said electric field intensity of said terahertz wave detected in said step (b) to an evaluation reference value that is smaller than an absolute value of said saturation value.

8. An inspection method for inspecting an insulating film formed on a surface of an inspection sample mainly made of a semiconductor material, the inspection method comprising steps of:
(A) detecting electric field intensity of a terahertz wave, said terahertz wave being generated by irradiating said inspection sample with light having a predetermined wavelength while different voltages are applied to said inspection sample; and
(B) specifying an applied voltage at which said electric field intensity of said terahertz wave emitted from said inspection sample becomes zero based on said electric field intensity of said terahertz wave detected in said step (A).

Assignees

• Screen Holdings Co Ltd
• Nat Inst Advanced Ind Science & Tech

Inventors

• Ito Akira
• Nakanishi Hidetoshi
• Mochizuki Toshimitsu
• Takato Hidetaka
• Shirasawa Katsuhiko

Classifications

• H10P72/0616

  Monitoring of warpages, curvatures, damages, defects or the like · CPC title

• H10P74/207

  Electrical properties, e.g. testing or measuring of resistance, deep levels or capacitance-voltage characteristics · CPC title

• H10W70/60

  Insulating or insulated package substrates; Interposers; Redistribution layers (leadframes H10W70/40) · CPC title

• H10P74/203

  Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects · CPC title

• H02S50/10

  Testing of PV devices, e.g. of PV modules or single PV cells (testing of semiconductor devices during manufacturing {H10P74/00}) · CPC title