X-Ray Reflection Data Analysis Update Information can be extracted from XRR data: - Film thickness - Roughness
Schematic of Experiment Geometry 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
Monitor Oscillation of Specular Reflection Peak during Sb Growth Double click the movie image or in slide show mode to play, watch the oscillation of the specular reflection peak during Sb growth Intensity of the peak Sb thickness: t = (# of intensity peaks* Sb film lattice) =21*1.1273 nm = 23.7 nm
Film Thickness vs Growth Time Two methods agree well, Confirm the Sb film growth is layer by layer 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
Analysis of the image frame after deposition: off-specular reflection peak Background Area Slice 1 Background was subtracted to obtain accurate data. 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.
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. Fourier Transform 23 nm