JPH072960U - Ellipsometer Method for Measuring Samples in Solution - Google Patents

Abstract

(57) [Summary] Measurement of a sample in a solution by an ellipsometer is almost impossible with a device that illuminates from outside the solution because the polarization characteristics change on the surface of the solution, making it impossible to measure using a container for measurement. The present invention, which can measure only one angle, has a liquid-proof structure on the light source side and the light receiving side, in which the lens barrel is directly immersed in the solution for measurement. [Purpose] To enable measurement of a sample in a solution with an ellipsometer at any angle. [Structure] Window glass (2) and (4) are attached to the light source side lens barrel (1) and the light receiving portion side lens barrel (3) respectively to form a liquid-proof structure, and the tip of the cylinder is placed in a solution (6) to prepare a sample (5). ) Is measured.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 According to the ellipsometer according to the present invention, it is possible to measure the physical properties of the thin film on the surface of the sample in the solution, for example, the refractive index and the film thickness of the oxide film on the surface of the IC wafer / stainless steel plate etc. under water. Can be done more easily.

[0002]

[Prior art]

 The measurement of a sample in a solution by an ellipsometer is a method in which the sample is fixed in the solution because the polarization characteristics change on the surface of the solution depending on the angle of incidence, which makes measurement impossible by the method of shining light from outside the solution. It was used. When light enters the solution due to the incident angle of light, a window is provided at right angles to the optical axis to avoid refraction / reflection on the surface of the solution. Meets and measures.

[0003]

[Problems to be solved by the device]

 Due to the measurement principle, it is necessary for the measurement by the ellipsometer to make the incident angle of light to the sample, and therefore, the light is reflected and refracted on the surface of the solution to enter the solution, and the polarization characteristics are changed, which makes measurement impossible.

[0004]

[Means for Attempting to Solve the Problems]

 In the present invention, both the light source side and the light receiving side have a protective window for liquid immersion at the tip of the lens barrel, and by inserting this into the liquid, there is no change in the polarization characteristics due to reflection and refraction of the light source side lens barrel. From the sample to the sample, and the light reflected by the sample was allowed to go straight to the light-receiving-side barrel, enabling measurement in the solution.

[0005]

[Work]

 By taking such a measure, the light does not pass directly through the surface of the solution, and the light goes straight through the protective window glass into the solution. It reached the sample without any reduction in the light quantity and became ready for measurement.

[0006]

【Example】

 FIG. 1 shows an embodiment of the present invention, in which the light guided from the light source side lens barrel (1) of the ellipsometer is guided to the solution (6) at a right angle through the window glass (2) and the sample in the solution ( By removing from the solution through the window glass (4) reflected by (5) and provided on the light-receiving side barrel (3), it is possible to avoid a change in the polarization characteristics on the surface of the solution. Fig. 2 is an optical path diagram for measurement with a conventional ellipsometer. In this case, when the light guided from the light source side lens barrel (1) of the ellipsometer enters the solution, the change in polarization property on the solution surface is shown. However, correct measurement is impossible with the light that has been reflected by the sample (5) in the solution and has reached the light-receiving-side lens barrel (3). Fig. 3 shows an example of a container used to measure a sample in a solution using an ellipsometer. A window (7) arranged perpendicular to the optical axis so that light does not reflect or refract at the required incident angle. The solution (6) is filled in the container (9) having the light sources (8) and (8), and the sample (5) is fixed in the solution. Is incident on the window (7) at a right angle, enters the solution, and the light reflected by the sample also passes through the window (8) at a right angle and is guided to the light-receiving-side barrel (3). Therefore, reflection / refraction does not occur, and only one set angle can be measured in one container, and it was necessary to prepare a container in which the window angle was changed for each measurement angle.

[0007]

[Effect of device]

 The present invention has made it possible to easily measure a sample in a solution and to measure at any angle.

[Brief description of drawings]

FIG. 1 Embodiment of the present invention

[Fig. 2] Configuration for measurement from outside the solution

[Fig. 3] Measuring method using a container

[Explanation of symbols]

(1) is the light source side barrel (2) is the window glass (3) is the light receiving side barrel (4) is the window glass (5) is the sample (6) is the solution (7) is the window glass (8) is the window Glass (9) is a container

Claims (1)

[Scope of utility model registration request] 1. An optical window is attached to the tip of the lens barrel on the light source side and the light receiving side in order to measure a sample in the solution with an ellipsometer, and a liquid-proof structure is provided, which is directly immersed in the solution. A method that allows the measurement of samples in solution.