Name: 橢偏儀和偏振光簡介 (Introduction to Ellipsometry and Polarized Light)
Uploaded: 2024-09-21T10:24:42.000Z
Duration: 4 min 31 s

Ellipsometry can measure the thickness and optical constants of thin films with high precision and accuracy.

橢偏儀可以高精度、高準確度地測量薄膜的厚度和光學常數。

To understand how ellipsometry works, we must start with a description of polarized light.

要了解橢偏儀的工作原理，我們必須從偏振光的描述開始。

This visualization shows a beam of light propagating towards you.

這幅視覺圖顯示了一束光向你傳播。

The electric field, shown as red vectors, oscillates perpendicular to the light beam direction.

電場（顯示為紅色矢量）垂直於光束方向擺動。

The magnetic field, shown as blue vectors, oscillates perpendicular to both the light beam direction and the electric field.

磁場（顯示為藍色矢量）垂直於光束方向和電場方向擺動。

The polarization state of a light beam is defined by its electric field, and therefore the magnetic field will not be displayed.

光束的偏振狀態由其電場決定，是以不會顯示磁場。

Imagine putting a screen at a fixed location in the beam path and watching the tip of the electric field vector versus time, as shown by the yellow ball.

想象一下，在光束路徑的固定位置放置一個螢幕，觀察電場矢量尖端與時間的關係，如黃色球所示。

In this example, the electric field oscillates up and down in a line, and the beam polarization state is called linear.

在這個例子中，電場在一條線上上下襬動，光束的極化狀態被稱為線性。

Waves can be added together to create new polarization states.

波浪可以相加，產生新的偏振態。

Here, the red and green waves are added in phase, resulting in a linear polarized beam with a different orientation.

在這裡，紅波和綠波相位相加，形成不同方向的線偏振光束。

When two waves with equal amplitudes are added 90 degrees out of phase, that is, the maximum amplitude of the first wave occurs when the amplitude of the second is zero, circularly polarized light is generated.

當兩個振幅相等的波相差 90 度相加時，即第一個波的最大振幅出現在第二個波的振幅為零時，就會產生圓偏振光。

If the two waves have different amplitudes or arbitrary phases, elliptically polarized light is generated.

如果兩個波的振幅或任意相位不同，就會產生橢圓偏振光。

This is where the term ellipsometry comes from.

Now let's consider the reflection of polarized light from a sample.

現在，讓我們來看看偏振光從樣品中反射的情況。

When light is obliquely reflected from a sample, the incident and reflected beams define a plane of incidence.

當光線從樣品斜向反射時，入射光束和反射光束會形成一個入射平面。

Light with its electric field vector oscillating in the plane of incidence is called p-polarized light.

電場矢量在入射面上擺動的光稱為 p 偏振光。

Light with its electric field vector oscillating perpendicular to the plane of incidence is called s-polarized light.

電場矢量垂直於入射面擺動的光稱為 s 偏振光。

The enabling principle of ellipsometry is that p- and s-polarized light reflect differently.

橢偏儀的原理是 p 偏振光和 s 偏振光的反射不同。

Ellipsometry measures the complex reflectivity ratio of p- and s-polarized light, and typically reports the results in terms of the ellipsometric psi and delta parameters.

橢偏儀測量 p 偏振光和 s 偏振光的復反射比，通常用橢偏儀的 psi 和 delta 參數來報告結果。

Tan psi is the magnitude of the ratio, and delta is the phase difference between the p- and s-reflected light.

Tan psi 是比值的大小，delta 是 p- 反射光和 s- 反射光之間的相位差。

To measure the ellipsometric parameters, an ellipsometer system must set the polarization state of the incident beam and detect the polarization state of the reflected beam.

要測量橢偏參數，橢偏儀系統必須設定入射光束的偏振狀態，並檢測反射光束的偏振狀態。

In the FilmSense FS1 ellipsometer, a polarizer in the source unit sets the incident beam to a linear polarization state, rotated 45 degrees from the plane of incidence.

在 FilmSense FS1 橢圓偏振儀中，光源裝置中的偏振器將入射光束設置為線性偏振狀態，與入射平面成 45 度旋轉。

The FilmSense FS1 detector unit contains a proprietary combination of beam splitters and optics, which split the beam into multiple beams and detectors, each sensitive to a different polarization component of the incoming beam.

FilmSense FS1 探測器單元包含一個專有的分束器和光學器件組合，可將光束抽成多個光束和探測器，每個探測器對進入光束的不同偏振分量敏感。

This provides fast, accurate, and reliable measurements of the ellipsometric parameters without any moving parts.

這樣就能快速、準確、可靠地測量橢偏參數，而無需任何移動部件。

The FS1 software plots the measured ellipsometric data as colored points on a 2D plane.

FS1 軟件將測量到的橢偏數據繪製成二維平面上的彩色點。

The four colors correspond to the four FS1 measurement wavelengths.

四種顏色對應四個 FS1 測量波長。

To determine film thickness or optical constants, it is necessary to analyze the measured ellipsometric dataset.

要確定薄膜厚度或光學常數，必須對測量到的橢偏儀數據集進行分析。

An optical model is defined, corresponding to the structure of the sample.

Model parameters, such as film thickness, are specified.

The optical model can generate an ellipsometric dataset, which is shown on the plot as open circles.

光學模型可以生成一個橢偏數據集，在圖中顯示為開放的圓圈。

At this specified thickness, the model-generated data does not fit the measured data very well, as quantified by the large fit difference value.

在此指定厚度下，模型生成的數據與測量數據的擬合程度不高，擬合差值較大就是證明。

When the Fit Data button is clicked, the software automatically searches for the parameter values, which minimize the difference between the measured and model-generated ellipsometric datasets.

點擊 "擬合數據 "按鈕後，軟件會自動搜索參數值，使測量數據集和模型生成的橢偏數據集之間的差異最小。

For a good fit, four bullseyes appear in the plot, the fit diff value is low, and sample parameters, such as film thickness, are determined with excellent accuracy.

擬合良好時，曲線圖中會出現四個牛眼，擬合差值較低，樣品參數（如薄膜厚度）的確定非常準確。

Thanks for watching this introductory video on ellipsometry and polarized light.

感謝您觀看這段關於橢偏儀和偏振光的介紹性視頻。

 To learn more about the features and capabilities of the FilmSense FS1 Banded Wavelength Ellipsometer, visit our website at www.film-sense.com

要進一步瞭解 FilmSense FS1 帶狀波長橢偏儀的特性和功能，請訪問我們的網站 www.film-sense.com。