Week+of+2-6+and+2-7

2-6-12 I came in today and began scanning a sample of octanethiol on Au(111). While i was placing the sample on the sample puck, i unscrewed the screw that holds the clip which holds the sample down too far. After I spent about ten minutes fixing this, I began scanning with 40.0 volts charged to the piezoelectric stack.The first image, "AA", was fairly decent. I zoomed into the upper left middle of this image. I stopped this scan about halfway through because it was so noisy. Afterwards, I changed the tip. The next image, "AB" had some well-defined features under a a general mass of noise. I zoomed into the bottom left quadrant of "AB. This image, "AC", was not the best but the I and P-gains used while scanning were quite high. I zoomed in to the area on the left side that included two hills and four valleys. This next image, "AD" was incredibly noisy. I changed the tip after. "AE" was a very clear looking picture. I zoomed into the bottom middle of this image. "AF" was decently noisy. I zoomed in to the upper right quadrant of "AF". This scan was incredibly noisy I stopped it about halfway through. 2-6-12AA media type="custom" key="12374416" This image showed a great deal of streaks in the upper middle region. There were a lot of features but they were veiled a general haze of noise which made me think that the tip was bad. The zoomed in scan of this image proved to me that this was indeed the case.

2-6-12AB media type="custom" key="12374420" The quality of the tip is less obvious in this image. The best indication of the tip would have to be the middle of the right side.There are some pretty decent looking features throughout but they are hard to see because of the scanning parameters used.

2-6-12AC media type="custom" key="12374422" This image has a very fuzzy nature to it. The features are very well defined but there is no insight into the surface of this image. There does not seem to be any Octanethiol molecules in this image, clearly showing the lack of quality of the tip. 2-6-12AD media type="custom" key="12374432" There is really nothing of interest in this image. It is quite noisy and the large difference in elevation between the hills and the surface in the upper half instantly removes a large portion of the image from being able to be viewed. There does not look like there is any Octanethiol molecules on this surface.

2-6-12AE media type="custom" key="12374438" This image is very interesting because of all of its well defined features. It is slightly harder to see the quality of the tip in this image because of the general lack of definition caused by the scanning parameters. The bottom right corner has the best indication of the quality of the tip but can only really be seen when the picture is enlarged. I zoomed in to the bottom middle region of this image.

2-6-12AF media type="custom" key="12374444" <span style="color: #222222; font-family: arial,sans-serif;">This image was incredibly noisy. There are a large amount of streaks throughout. There does not appear to be any insight into the surface of the gold or into the structure of any Octanethiol molecules. <span style="color: #222222; font-family: arial,sans-serif;">2-7-12

I came in today and began scanning the sample of Octanethiol on Au(111) from yesterday that Natalie prepared. My first image was very bljurry. I cut the tip afterwards. I am scanning with 40.0 V charged to the piezoelectric stack. The next scan was also very blurry. I stopped the scan and changed the tip about halfway through. The next scan was also incredibly blurry. I stopped it about 1/5 of the way through and cut the tip. I zoomed in to the top left quadrant of "AB". It was fairly blurry but I scanned with only 25.00 nm on the Z-range so this accounted for much of the lack of definition. "AC" was decently interesting. It was fairly noisy. The features were quite well-defined. I zoomed in to the top middle region of this image. This scan was awful and I stopped it about 1/4 of the way through and changed the tip. "AD" could either be incredibly noisy or hvae lots of well-defined Octanethiol molecules. I decided to laser it. //__**1st Laser Attempt**__// I brought the voltage down from 40.0 V to 5.0 V. However, as I was bringing the voltage down, I noticed that the sample had crashed into the tip. Despite this, I shot the laser for fifty seconds. I then let it cool for five minutes. After it cooled, I withdrew the sample using the STM software's withdraw feature, brought the voltage back up to 40.0 V, and then approached with the software. The after scan kept bottoming out and I could unfortunately never finish the scan. 2-7-12AA media type="custom" key="12386816" The many shining dots of this image coupled with its general lack of definition clearly show this image to have been scanned with a poor tip. The edge surrounding the large area that covers most of the left side shows general disarray and a lack of definition. There does not appear to be any potential for this image and that is why I changed the tip. 2-7-12AB media type="custom" key="12386818" This image reveals a good amount of features under the general haze of the image that is a consequence of the very large Z-range that I scanned with. There is not much obvious noise or differentiation on the surface here and this makes it hard to tell whether the tip is good or bad. However, the area surrounding the large valley in the bottom right quadrant suggests through its streaks that the tip is bad. I zoomed in to the upper left quadrant. 2-7-12AC media type="custom" key="12386820" The sandy look of this image as a whole shows fairly clearly the quality of the tip. Some of the valleys in the top middle region slightly show this with the faint streaks coming off of the top parts of these features. There does not appear to be any Octanethiol on this surface and the zoomed in scan confirmed this. 2-7-12AD media type="custom" key="12386822" As I take a more detailed look at this image, it is more apparent that this image was in fact just incredibly noisy. This is very obvious in the bottom right corner with the streaks coming off the side of the large hill. I probably should have not shot the laser at this image but I should have changed the tip and attempted to get a better looking image with the little time that I had left.