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.

Soft X-ray Photoelectron Spectroscopy (SX-XPS, 0.15~2 keV)

 

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。

Soft X-ray Photoelectron Spectroscopy (SX-XPS, 0.15~2 keV)

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

Soft X-ray Photoelectron Spectroscopy (SX-XPS, 0.15~2 keV)

Transfer Vessel Specifications

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

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

(0)