US-12625005-B2 - Radiation temperature measurement device and radiation temperature measurement method

Abstract

There is provided a radiation temperature measurement device that accurately measures a temperature of an object being measured, and that includes two infrared detection units that detect mutually different infrared wavelength bands, a spectral characteristics data storage unit that stores spectral characteristics data showing a transmittance and a reflectance of each of the objects being measured, and a temperature calculation unit that, based on infrared ray quantities detected by each of the two infrared detection units, and on the transmittance and reflectance of each of the objects being measured, calculates the temperature of each of the objects being measured.

Inventors

• Sho FUJINO
• Koji Tominaga

Assignees

• HORIBA, LTD.

Dates

Publication Date

20260512

Application Date

20220308

Priority Date

20210409

Claims (6)

1. 1 . A radiation temperature measurement device that measures a temperature of an object being measured, comprising: two infrared detection units that are provided at a processing chamber configured for processing the object being measured, and that detect infrared ray quantities in mutually different infrared wavelength bands; a spectral characteristics measurement unit that is provided at a spectral characteristics measurement chamber that is different from the processing chamber, and that measures a transmittance and a reflectance of the object being measured; a spectral characteristics data storage unit that stores spectral characteristics data that indicates the transmittance and the reflectance obtained by the spectral characteristics measurement unit; and a temperature calculation unit that, based on the infrared ray quantities detected by each of the two infrared detection units and on the transmittance and the reflectance of the object being measured, calculates the temperature of the object being measured.
2. 2 . The radiation temperature measurement device according to claim 1 , wherein the spectral characteristics measurement unit measures the transmittance and the reflectance of the object being measured using either all of or a portion of the infrared wavelength bands detected by the two infrared detection units.
3. 3 . The radiation temperature measurement device according to claim 1 , wherein, in a case in which the transmittance of the object being measured is equal to or greater than a predetermined value, the temperature of the object being measured is calculated using the infrared ray quantities detected by the two infrared detection units, and, in a case in which the transmittance of the object being measured is less than the predetermined value, the temperature of the object being measured is calculated using an infrared ray quantity measured by one of the two infrared detection units.
4. 4 . The radiation temperature measurement device according to claim 1 , wherein the temperature calculation unit corrects the temperature of the object being measured using a temperature correction parameter originating in the processing chamber.
5. 5 . A radiation temperature measurement method for measuring a temperature of an object being measured, comprising: detecting, by two infrared detection units that are provided at a processing chamber configured for processing the object being measured, infrared ray quantities in mutually different infrared wavelength bands; measuring, by a spectral characteristics measurement unit that is provided at a spectral characteristics measurement chamber that is different from the processing chamber, a transmittance and a reflectance of the object being measured; and calculating, by a temperature calculation unit, the temperature of the object being measured based on the infrared ray quantities detected by each of the two infrared detection units and on the transmittance and the reflectance of the object being measured.
6. 6 . The radiation temperature measurement device according to claim 1 , wherein the spectral characteristics measurement unit measures the transmittance and the reflectance of the object being measured before the object being measured is transported into the processing chamber.

Description

TECHNICAL FIELD The present invention relates to a radiation temperature measurement device and radiation temperature measurement method. TECHNICAL BACKGROUND Conventionally, a non-contact type of radiation thermometer has been developed that detects infrared rays emitted from an area being measured using an infrared sensor (for example, a thermopile), and then measures the temperature of the area being measured using the detected infrared ray quantity. In this radiation thermometer, not only the area being measured, but also a background of that area falls within the measurement field of view of the infrared sensor, so that it is difficult to accurately measure the temperature of the area being measured simply by detecting infrared rays reflected from the area being measured. DOCUMENTS OF THE PRIOR ART Patent Documents Patent Document 1 Japanese Unexamined Patent Application (JP-A) No. 2017-90351 DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In consideration of the above-described problem, the inventors of the present application devised a radiation temperature measurement device having two infrared detection units which detect mutually different infrared wavelength bands, and that calculates a temperature of an area being measured based on the infrared ray quantities detected by these two infrared detection units. More specifically, the temperature of an area being measured is calculated in the following manner. A total quantity of infrared rays in a predetermined wavelength band that is irradiated onto the infrared detection units from the area being measured is the sum of infrared rays A1 from the area being measured, infrared rays A2 from the background of the area being measured, and infrared rays A3 reflected by the area being measured. In a case in which the infrared detection units and the area being measured are directly facing each other, A3 is formed by the infrared rays from infrared detection units and is consequently a known value. Accordingly, a ratio R between A1 and A2 is found by R=A1/A2. In other words, R is the emissivity/transmittance of the area being measured. Because the detected infrared wavelength band differs between the two infrared detection units, the ratio R between A1 and A2 is separated into R1 and R2 in the respective infrared detectors. Accordingly, the temperature of the area being measured is calculated using simultaneous equations or a bisection method from the infrared ray quantity detected by one of the infrared detection units and the infrared ray quantity detected by the other of the infrared detection units, and from the known ratios R1 and R2 in the respective wavelength bands. Note that it is necessary that the ratios R1 and R2 in the respective wavelength bands be determined in advance. Moreover, in a case in which R1=R2, it is not possible for simultaneous equations to be calculated, and neither is it possible for the temperature of the area being measured to be calculated. Here, in a case in which the temperature of a silicon substrate, for example, is being measured, then it is known that a silicon substrate has a high transmittance, and that, when the temperature of a silicon substrate is 600° C. or less, the transmittance thereof changes in accordance with the temperature. In particular, when measuring the temperature of a silicon substrate which is at 200° C. or less, the measurement is affected by infrared rays from the background due to the transmittance thereof, so that measuring the temperature is not considered possible in this case as well. In particular, in a semiconductor manufacturing device, the temperatures of a variety of different types of subjects (such as substrates having varying quantities of dopants, substrates having oxide films, nitride films, or metal films formed on the surface thereof, and substrates having resist films formed thereon) are measured, and it difficult for R1 and R2 to be determined. Moreover, even if R1 and R2 are known values for silicon substrates that have undergone the same processing (for example, silicon substrates on which a 200 nm SiO2 (silicon oxide) film has been formed), in a case in which these substrates are processed in a semiconductor manufacturing device, R1 and R2 become changed due to differences between the film thicknesses of the substrates, so that it is not possible to perform an accurate temperature measurement. The present invention was conceived in order to solve the above-described problems, and it is a principal object thereof to enable the temperature of an object being measured to be measured accurately. Means for Solving the Problem In other words, a radiation temperature measurement device according to the present invention is a radiation temperature measurement device that measures a temperature of an object being measured, and is characterized in being provided with two infrared detection units that detect mutually different infrared wavelength bands, a spectral ch