I am doing STM with cleavage SrRuO3.I prepared the STM tip through scanning Cu film and Si(7×7) separately，and the image is fine and can see Si(7×7) clearly. So I think that I have prepared the tip，but when I change the sample to SrRuO3 to scan it，the quality of the image is poor and the left edge of the forward imaging is always high. It is weired! What the reason of this? Can you help me if you have any idears?
Here is a nonexpert comment: I suspect that with your scanning mode the tip always starts scanning from the left side going toward right of scanline. Probably you use a constant current scanning mode. Then, when tip is moving over oxided part, the current is droping drastically leading to crash of the tip on the surface. Maybe try do scan with constant height mode? Or plese specify more details...
I agree with Konrad, the "bad metal" character of SrRuO3 makes it more difficult to have a high tunnel current. The Si is much better for that. So you have to find different conditions for the SrRuO3. That means you have to play with the voltage a lot, change the tunnel current to small currents and apply voltage peaks in between to clean the tip. Dont scan to small, it helps to clean the tip also if you scan very large images for 1h or so, like 5000Ax5000A. Then go back to 1000Ax1000A or so, scan with low currents and high voltage applying 9V voltage bursts for a second or so and repeat that on different areas a lot. It can take days on the same sample to find the perfect conditions. It also might be in the end that the SrRuO3 surface is simple not very smooth but you have to try. Dont give up! Good luck!
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