Soft X-ray Photoelectron Spectroscopy (SX-XPS, 0.15~2 keV)
X-ray Photoelectron Spectroscopy (XPS) is an inspection technique to used for quantitative determine atomic composition and its chemistry located near the sample surface. The working principle is irradiating a monochromatic X-rays on the sample to kick out photoelectrons and measure the kinetic energy of electrons to determine core level of elements which these electrons come from.

同步輻射光源的優點在於,可以非常方便的調整入射樣品的X光能量。依據左圖的電子動能與平均自由路徑的圖示來看,不同的X光能量,其所檢測的樣品有效深度也將改變。
傳統實驗室的XPS縱深分析,必須搭配離子束處理來去除表面材料,才能量測較深層的訊號,然而這樣也破壞了樣品結構,並可能影響樣品的特性。
同步輻射XPS可以利用連續的能量調整來探測不同深度的樣品訊號,並且無須破壞樣品的表層結構,從而保證樣品結構的完整性以及訊號的真實性。

Beamline Specifications |
||
Item |
Value |
Note |
X-ray Energy (keV) |
0.15 ~ 2 |
G1 (500 l/mm): 0.7~2 G2 (1000 l/mm): 1~2 G3 (500 l/mm): 0.15~0.7 |
X-ray Spot Size (mm) |
1 x 1 |
|
X-ray Flux (photon/sec) |
1 x 109 ~ 2 x 1010 |
See figure |
Sample Plate Size (mm) |
15 x 18 (Usable 14 x 14) |
Maximum sample size limited to 12 x 12 mm |
Detector |
PHOIBOS 150 CCD |
SPECS |
Transfer Vessel Specifications |
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Item |
Value |
Note |
Transfer Condition |
Purge N2 gas |
Sample will prepare and mounted on sample plate in groove box with dry N2 flow at low oxygen and water vapor condition |
Maximum Sample Plate |
7 |
Each plate can mount 1~4 sample depend on its size |
Maximum Sample Height (mm) |
5 |
|
Material of Sample Plate |
Al, Fe, Mo, Ti, Ta |
Depend on measure energy of X-rays |
Experimental Details |
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Item |
Value |
Note |
Pumping Down Time (min) |
60 |
Maximum 7 sample plate in one vacuum vessel |
Sample Transfer Time (min) |
15 / 15 |
In and out of analysis and load-lock chamber |
Sample Alignment Time (min) |
5 |
This will be apply multi-times when change energy |
Change Grating (min) |
10 |
Exchange between G1, G2, and G3 gratings |
Change Probe Energy (min) |
10 |
For depth profiling (3-spectra for 20 min and 5-spectra for 40 min) |
Spectrum Scan Time (min) |
5 ~ 15 |
5-scan average, cover 20 eV range |
Detection Limit (ppm) |
< 1 |
Need longer aquicticon time |