Apparatus and method for non-contact sample analyzing using teraherz wave

Patent metadata

Field	Value
Publication number	US-2016305995-A1
Application number	US-201615130545-A
Country	US
Kind code	A1
Filing date	Apr 15, 2016
Priority date	Apr 17, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

Disclosed are an apparatus and a method for non-contact sample analysis using terahertz waves. The apparatus includes an emission unit radiating terahertz waves onto a sample provided with a conductive material layer, and a receiving unit receiving terahertz waves reflected from the sample or terahertz waves passing through the sample. The apparatus further includes a characteristic analysis unit including at least one selected from a group consisting of a sheet resistance analysis unit analyzing a sheet resistance of the conductive material layer, a coverage density analysis unit analyzing a coverage density of the conductive material layer, a component analysis unit analyzing a component of the conductive material layer, and a thickness analysis unit analyzing a thickness of the conductive material layer by using the received terahertz waves, a display unit displaying a result derived from the characteristic analysis unit as an image, and an input unit configured to input information to the characteristic analysis unit.

First claim

What is claimed is:

1 . An apparatus for non-contact sample analysis, the apparatus comprising:
an emission unit radiating terahertz waves onto a sample provided with a conductive material layer; a receiving unit receiving terahertz waves reflected from the sample or terahertz waves passing through the sample; a characteristic analysis unit including at least one selected from a group consisting of a sheet resistance analysis unit analyzing a sheet resistance of the conductive material layer, a coverage density analysis unit analyzing a coverage density of the conductive material layer, a component analysis unit analyzing a component of the conductive material layer, and a thickness analysis unit analyzing a thickness of the conductive material layer by using the received terahertz waves; a display unit displaying a result derived from the characteristic analysis unit as an image; and an input unit configured to input information to the characteristic analysis unit.

2 . The apparatus of claim 1 , wherein the sheet resistance analysis unit derives the sheet resistance of the conductive material using Equation 1:
log 10 R sh =aX+b,   [Equation 1]
in Equation 1, X is a reflection ratio or a transmission ratio obtained by using the received terahertz waves, a and b are values depending on a material forming the conductive material layer, and Rsh is the sheet resistance of the conductive material layer.

3 . The apparatus of claim 2 , wherein:
the characteristic analysis unit further includes a database; the values a and b shown in Equation 1 are reference values stored in the database to correspond to the material forming the conductive material layer; and the sheet resistance analysis unit is deriving the sheet resistance by: deriving a reference value a and a reference value b of Equation 1 from the database on the basis of information about the material forming the conductive material layer that is input from the input unit; and inputting the reflection ratio or transmission ratio obtained by using the received terahertz waves, the reference value a, and the reference value b into Equation 1.

4 . The apparatus of claim 2 , wherein:
the sheet resistance represents a sheet resistance of each grid-shaped virtual region on a surface of the conductive material layer; and the display unit displays sheet resistances derived from the sheet resistance analysis unit as two dimensional images with different brightness levels depending on a magnitude of the sheet resistance of each of the regions.

5 . The apparatus of claim 1 , wherein the component analysis unit derives a type or a mixing ratio of a material that forms the conductive material layer using Equation 1:
log 10 R sh =aX+b,   [Equation 1]
in Equation 1, X is a reflection ratio or a transmission ratio obtained by using the received terahertz waves, a and b are values depending on the type or the mixing ratio of the material forming the conductive material layer, and Rsh is the sheet resistance of the conductive material layer.

6 . The apparatus of claim 5 , wherein:
the characteristic analysis unit further includes a database that stores a reference value a and a reference value b that correspond to the type or the mixing ratio of the material forming the conductive material layer; and the component analysis unit is deriving the type or the mixing ratio of the material forming the conductive material layer by receiving sheet resistances of two regions of the conducive material having thicknesses different from each other, receiving reflection ratios or transmission ratios obtained using terahertz waves received from the two regions, calculating a linear extrapolation function as shown in Equation 1 based on the reflection ratios or the transmission ratios and the sheet resistances of the two regions to calculate the value of a and the value of b of Equation 1, and comparing the calculated value a and the calculated value of b with the reference value a and the reference value b stored in the database.

7 . The apparatus of claim 1 , wherein the coverage density analysis unit derives the coverage density using Equations 2 and 3:

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Assignees

• Industry-Univ Coop Found Hanyang Univ

Inventors

• Kim Hak-Sung
• Chung Wan-Ho
• Park Sung-Hyeon
• Kim Dong-Hyun

Classifications

• G01B11/06 Primary

  for measuring thickness {; e.g. of sheet material (thickness measurement by thermal means G01B21/085)} · CPC title

• G01R27/02 Primary

  Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant (by measuring phase angle only G01R25/00) · CPC title

• G01R31/309 Primary

  of printed or hybrid circuits {or circuit substrates} · CPC title