X-Ray Reflection Data Analysis Update
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Transcript of X-Ray Reflection Data Analysis Update
X-Ray Reflection Data Analysis Update
Information can be extracted from XRR data: - Film thickness - Roughness
Pilatus 100K Detector System
Pixel size 172 x 172 μm2
Format 487 x 195 = 94 965 pixels
Active area 83.8 x 33.5 mm2
Counting rate > 2x106 counts/s/pixel
Energy range 3 – 30 keV
Readout time < 2.7 ms
Framing rate > 200 Hz
Ki is the direction of incident X-ray, pointing to sample.The recorded image is the reflected beam intensity image
Schematic of Experiment Geometry
Sb thickness: t = (# of intensity peaks* Sb film lattice) =21*1.1273 nm = 23.7 nm
Specular reflection peak
Double click the movie image or in slide show mode to play, watch the oscillation of the specular reflection peak during Sb growth
Inte
nsity
of t
he
peak
Monitor Oscillation of Specular Reflection Peak during Sb Growth
Film Thickness vs Growth Time
Film thickness obtained methods:
Quartz crystal microbalance: Directly from the calibrated QCM read out. Specular Reflection beam: Count the peak number and calculate the thickness
Two methods agree well, Confirm the Sb film growth is layer by layer
Slice 1
Linear scale Intensity vs pixel #
Log scale Intensity vs pixel #
Convert pixel # to Qz value, plot Intensity vs Qz.Note that the x axis is reversed due to the experiment set up, fringes along Qz can be observed.
Background Area
Background was subtracted to obtain accurate data.
Analysis of the image frame after deposition:off-specular reflection peak
Fourier Transform
23 nm
Transformed peak position tells Sb film thickness around 23 nm, agree well with thickness obtained from quartz crystal microbalance monitor during growth.
The signal is not so clear, may due to the background is not perfectly handled. Need to further modify the codes for background consideration.
Roughness (peak broaden), will be easier when the peak is sharper.