Sputter chamber shutters working

I worked with Ryan to check that the shutters are properly functioning and controllable through LabView.

continuing testing

so far everything checks out, now I need to hook it up to the sputter chamber and make a labview program to control the valves.

close to testing

I was delayed by some of the old solder connections on the main switch as they kept breaking off and they took a lot of time to fix when they did. Now I need to connect the power supply and test. A simple test program in lab view will be quick to make but Ryan and I will need to work out a way to make it more mistake resistant and assist me in venting the chamber to do a full test when ready.

finally some progress

Keegan helped me with some of the sputter chamber wiring. i spent lots of time figuring out that soldering is not going to work for us. so i learned about wire wrapping and got some supplies from John and it's going much better. soon we can test the USB and then make some films.

continuing on sputter system

I have continued working on the sputter system. I need to investigate wire connectors as the ones currently on the solenoid valves are not able to be disassembled. I talked with Ryan about analyzing the latest pump probe data as Joel did in his thesis. I need to finish reading the relevant sections and process the data Ryan sent me.

Out sick

I have been out sick all this week but I talked with John on Monday and he had the switch we needed lying around so he gave it to us.

not much progress

I worked with Ryan earlier this week to get the pump probe working. I talked to Ying about a circuit for the sputter control box. 480 has kept me from doing more this week.

still working on the electronics

I was busy writing a paper this week and made only minor progress with the electronics. I need to talk to John about a way to switch between labview and manual switches inside the box. Homework should be minimal now and I will get to doing pump probe.

Found a case

Now we have a case to put all the electronics to control the valves in. I need to remove some of the old components and put in the new. I will also make a lab view program that controls the valves when I get the hardware working.

sputter chamber valve control

The circuit works and the current parts should be sufficient. Pending Keith's return I will get a rack mount box from the storage room. The electronics shop should have all that I need to finish(may need to look into ordering switches for manual override but I have yet to see what all is there).

Valve control

I talked with Ying about the circuit and she was concerned about how much power the valve would draw. I will have to test it with our exact valves as she is familiar with different ones. At worst we would just need a few more of the ICs, uln2003a, to power all of our valves.

My test circuit is almost done. If all goes well I will test it with one of the unused valves or a non critical one like the sputter shutter.

still busy with smart surfaces

smart surfaces keeping me busy

I have not had a chance to make the circuit for sputter chamber valves yet.

Smart Surfaces is still keeping me busy

Did not get a chance to wire up the control circuit for the valves.

smart surfaces troubles

There has been some group problems this week in smart surfaces that have taken up all my time this week so I have not made any progress.

galvo control

Cambridge Technology has a software program that can be used with one of their controller boards to control the galvos. LINK This is probably expensive as they list no prices and we have the digital controller that John Nees built which likely does what their hardware controller does.

Using labview to control a mirror has been done by Ashcroft and Oosterkamp LINK but they only have one galvo and step the stage for their second axis. It may be worthwhile to look more into what they did and contact them.

still sick

Still no progress due to illness.

out sick

No progress due to illness.

Trying to talk to someone in tech support at Cambrige Technology

I have tried unsuccessfully to talk to the tech support guy at Cambrige Technology, the manufacturer of our galvos and controller.

The components ordered for making the pneumatic valves controllable in Labview have arrived. I will talk with Ryan about building it and how the labview will be setup.

Diagnosing sputter chamber computer

The sputter chamber computer failed last week. With Ryans assistance I took the computer apart and was able to find that a MOSFET in the power supply failed. I have ordered a replacement for $7 and I expect it to arrive within a week. Soldering in the new part should make the repair barring other problems we don't know about.
I will try to see if parts has another computer/power supply to have as a backup.

I have continued to work on the galvo controller and it is capable of relative and absolute motion. Now I need to have Ryan show me how he imports images and controls the shutter so that I can have the galvos make an image.

I have found an alternate supplier for the rough pump oil but I still need to find a rebuild kit.

Break

Nothing new since last week. I will look into the pump oil and rebuild kit. I am still working with Ryan on the Galvos.

Galvos have more functions

Galvos have the ability to go to absolute position and have a log of most recent positions. I still need to find a different supplier for the rough pump oil.

Galvos functioning

I worked John Nees and Ryan to get the galvos operational. The mirrors are working with labview 10. I will look again into controlling them with labview 8 but it is likely that we will need to get a license for labview 10. Next I will work with Ryan to get a program to give us more useful control over the mirrors than the manual position entry I have now.

Regarding the oil for the rough pump, ALCATEL requires a minimum order of $50. 1 gal of oil is $19 so we can get 3 and have oil for future changes or I can look into a different supplier.

Galvos

I worked with John Nees on Monday and got the galvos wired to the new controller. The mirrors will center themselves correctly when powered on and is a good indication that the hardware will work as expected once the software for the controllers works. The labview we currently use does not work with the controllers and I will use a trial of the new version to see if it has what we need.

I called the rough pump manufacturer and found out what kind of oil the pump needs.
It needs an A119 mineral oil and is ~$6 a liter and one or two liters should be enough. I can order it this week.

controllers arrived

The controllers arrived on Monday and no visible damage to the package so both should be in working order. I need to read up on how they work and talk to john nees about how they will work with the power supply. I have exams and projects this week so I will likely not be able to do much with them until the weekend.

I helped Ryan and Abere move out of the cubicle area last weekend. I came across many old computers and Ryan suggested that I back up the data from those hard drives to allow us to dispose some of the older of the 5 or so machines. I will look into getting more oil for the rough pump on the sputter chamber as it is running low.

CuPc and Galvos

Casey and I attempted to deposit CuPc in the static field. Our Faraday cage for the CuPc nozzle was ineffective and this lead to the overheating of the CuPc and clogged the nozzle. The glass blower was not available yesterday to clean the nozzle so we will try today and if need be tomorrow to get it cleaned. We will improve our Faraday cage and try again.

I ordered the digital I/O cards on Monday and the standard shipping would mean they should be in by the end of the week but I suspect that the impending snow may mean they arrive early next week.

working on grounding electrical system

I met with Casey and Peter last week to go over our electrical setup. Peter recommended some changes in how we make electrical ground connections, I did this yesterday. He also suggested smoothing our sample to reduce arcing as we were getting a higher stable field with out a sample present. This is likely due to the field enhancement on the sharp edge of our sample.
I just talked with John Nees about the controller and it sounds like a National Instruments USB controller will be suitable. We need two, one for each mirror, at $100 each. I will confirm the exact model with John and Peter then place the order.

Capacitor and Galvos

I stopped the capacitor from arcing across the edges. Now the sample area is where it arcs. It seemed to be localized to one area and I will try to smooth it further to get a higher field. Currently a 1.8MV/m is fairly stable.
I met with Peter and we have discussed how the mirrors are controlled and how to implement controls similar to what we use already for the stage. The next step is going to be creating a test setup and installing the software on one of the computers.

Galvos and Capacitor

I got in touch with Peter Diehr as he has worked with the galvanometric mirrors previously with McClain. We should be able to meet later this week to talk about getting them working. Last I talked to John Nees he is still looking for the card that interfaces with the computer. As long as it can be found soon this should not be too much a problem as I have to read the instructions on all the components.
I have tested the capacitor and the first part to arc is the sides and not across where the sample is. I want to try and insulate this area or adjust the setup in some way to try and get a higher electric field across the sample area.

Back from Break

I talked to Ryan yesterday about making an improved setup for running experiments in water based on a paper Abere found. Ryan has also mentioned that I may be able to help him with finding and programming some galvanometric mirrors to give us more control over the beam.

setup for molecular alignment

Casey and I recently set up most of the molecular alignment experiment. The nozzle was not at proper height using the stand from the Shtein group so we made one that can be adjusted to the proper height. A prism and wave plate, to adjust the beam power, need to be added yet and final alignment done before running the experiment. The next time Casey and I are in lab we should be able to do all of that.

starting sop

I smoothed the edges of the capacitor and I looked at the SOP that Ryan made recently so I can make the one for the capacitor in the same format. I am busy with exams and I will be gone all weekend. I hope to work on the SOP in the car. I need to find some braided wire to ground the setup, I think there is some in the lab that is of suitable length but I need to find it.

Ready for testing

I finished machining and assembling the capacitor. Next I will attach it to the HV supply and test it out before Casey and I use it in an experiment. If the setup goes well I should be able to run experiments next week. I do want Ying Qi to look over my setup once I have it assembled to look for any safety concerns.

done maching

I was able to finish machining the capacitor holder. The final few steps are to attach leads to the plates, attach the fixed plate, and attach the flap that will hold the sample down. This should be some straight forward soldering and gluing. This weekend I want to research more about HV safety and begin to write a SOP.

Capacitor

I rounded and polished the capacitor plates so this should make a more uniform electric field than rough plates. The mills have been taken when I was in the shop so I was not able to do the last bit of machining on the capacitor. If the mills are available I should finish today or this weekend.

I have not found anything about our power supply in my searching online but I will try to get into contact with someone in the lab where we got it to see if they have any info about it.

continuing with capacitor

I am still working on making the capacitor. I have made some adjustments to the design to make it easier to swap samples. The rest of the fabrication is going well.

On Monday I talked again with Ying about the HV. She gave me some instructions from her HV supply and I hoped to get some safety information from them but they were more about the specific operation of the machine and did not have much about general safety. I think I will look online for more general information that can be applied to our setup and to include in the SOP.

molecular alignment

I have begun to make the capacitor. The nylon is cut and the capacitor plates are roughed out but need to be rounded and smoothed yet. Thursday I hope to do a dry fit and check clearances and figure out how I will mount it to the stage.

I talked to Ying about HV training and she will be available to teach me some time later this week. Once I am trained and have the capacitor made I will write the SOP.

Working with Ryan

I am still busy with class but I met with Ryan to use the TEM wednesday morning and we looked at some carbon nanotubes. I also read some about the self focusing that occurs in water and had a nice explanation from Max Shtein. I think I have a good idea about how this occurs and what it means for the fluence at the sample. This morning I worked on adding some functionality to the labview program that controls the stage movement. When finished the added functions should allow me to make particles at the calculated fluence and decrease the necessary amount of laser time.

Busy with classes

I was not productive this week. I was not able to meet Ryan to use the TEM or learn about LIBS due a final paper draft, and a dentist appointment. I will attempt to use the TEM with Ryan to get some images of the nanoparticles that I last week but classes are coming to an end so I do not know if there will be time to do this.

Made some nanoparticles

Yesterday I met with Ryan in VanVlack to use the SEM on some of his Ni samples. This was quite interesting as I had not used an SEM before. After that we went to the lab where I got some experience in setting up the lenses and mirrors before making some GaAs particles. I will need to do some programming in lab view to make Ryan' program for adjusting the sample stage faster and simpler. I read a few papers this week that did not really have any new and interesting information. I did some research into cavitation as a follow up to some of the papers I read last week. I think I have a basic understanding of the process and how it may apply to making particles with our laser.

Some interesting experiments

I was busy with homework and projects this week so that kept me out of the lab but I did read a few papers, the interesting ones I have already posted. One paper was about the use of a two pulse setup to make particles. They used a primary perpendicular pulse and a parallel secondary pulse to make the particles. This made for smaller and more uniform distribution of sizes. They do not mention their pulse duration but I suspect that it is in the ns range as they use a Nd:YAG laser.
The one of the other papers I posted indicates that there is particle formation due to cavitation and the direct ablation of the substrate. They took some shadowgraph images from 0-300µs that show the formation and collapse of a bubble and this makes more particles. This aligns well with another paper that says there may be multiple formation mechanisms since the particle sizes moderate fluences (100-400J/cm2) do not have a good fit to a single gaussian distribution.
I will need to learn more about cavitation and how that process can form particles.

TEM

This past Wednesday I met with Ryan to try and get some images of some tubes that he and Jim had made. We did a lot of searching for them but most of the grids were blown out by the laser or some other reason. I did some reading about using the TEM before we met and I learned some of the theory behind the microscope and some good advice about how to align and adjust the lenses. We practiced aligning the beam and I am glad we did as the resolution was much better than the last time we used the machine. The sample did not shift across the screen when changing the magnification, which I now know to be caused by a misaligned beam, which we had previously.Our improved technique made investigating interesting areas much faster and easier, although there is still room for improvement.
Ryan and I also discussed replicating the work of others. We can use some of the samples that he has already made to work on characterizing the particles. Ryan will teach me how to use the sputtering system so that I will be able to make some of the alternating thin film samples to test once we are comfortable with making and characterizing some pure metal samples.

lots of homework

All my classes had large assignments due this week so I did not have time to doing anything but thinking.

Data backup and lab time

Last weekend and early this week I was investigating possible components for the backup and storage computer. Currently I am thinking that OpenSolaris will be a good operating system as it is very simple to implement software RAID with redundancy. Adding more drives and management in general is a trivial task based on what I have read of the ZFS file system used in OpenSolaris.
This wednesday I met with Ryan at EMAL to use the TEM all morning. I learned about the start up and setup of the machine as we were first to use it that day. I learned what most of the knobs and buttons do but there is certainly more to learn and I hope to go again with Ryan. That afternoon we returned to EMAL and used the AFM to take some images of some of his bare nickel sample. I learned about how to setup that machine and some of the settings that alter image quality.
Today I read a lengthy paper that has lots of information about the absorption spectrum of the nanoparticles and how that effects the smallest achievable size of the particles. I have posted this to ctools a it seems to have lots of information.

Au and Ag colloids

Exams have kept me busy this week but I have read some interesting papers. The papers have clear diagrams of the experimental setup used and some nice TEM images of the nanoparticles that were produced. Both papers I have posted to the ctools page use a similar setup to ours. One setup does use a magnetic stirrer to mix the sample with the intention of having the particles be exposed to multiple pulses to narrow the size distribution and try to get rid of large agglomerates. They also aged the colloids for a few months then evaluated the sizes again. The aging narrowed the size distribution and reduced the number of large agglomerates. I think it would be interesting to see if this is actually due to time or if centrifuging a sample would have the same effect.
The other paper details why the colloids are stable. They say that the colloid is so stable is because the zeta potential is large (-35mV). This means that the Au nanoparticles in water are charged and thus repel each other in water. This electrostatic repulsion keeps the particles separated and thus they do not clump together and precipitate out. I am interested to see if other papers claim that aging does narrow the distribution of sizes and I will search for a bit information about about the zeta potenital and the stability of the nanoparticle colloids.

Read some more papers

I have been trying to catch up on homework from being sick. I have gotten to read some of the papers that I found the other week. I found one that detailed a two perpendicular pulses to make nanopartices. They do not use fs lasers and so it may still be worth repeating. I have also found a paper that details how they put the particles on a TEM grid. I have also found an interesting paper about a significant increase in thermal conductivity of water by suspending a small amount of Au nanoparticles. I plan to continue reading papers and meet with Ryan to make some nanopartices. I have been accepted for the SURE program put on by Rackham which will let me do research here this summer.

Found some papers

I am feeling somewhat normal now and I used the search terms from an article that I have previously read and it yields much more relevant results. I have found 20 possible articles from the first 100 results. Using my "old" search terms I was finding around 5-10 possible articles per 100 search results. The new and improved search terms will make future searches more productive and less time consuming. Next I will read the bunch of papers from my latest search and reschedule time with Ryan to make some nanoparticles.

Not been feeling well

I have been ill since the end of last week and have not been doing much.

Paper searches

       This morning I met with Ryan. He has read the paper about irradiating a wire sample end on; we concur with Steve that the paper is a bit sketchy. However, we are intrigued by their setup and would like to attempt to repeat it. Ryan and I discussed a method to use 50um thick films and irradiate them from the side in order to approximate an end on wire hit. We are interested in doing a pump-probe experiment in order to image the ejecta plume and confirm a difference between that and a bulk sample, something that was lacking in the paper we read. Later, Peter brought to our attention that one of our mirrors that directs the beam to the lower level lab was not very reflective. So we found some unused mirrors and I got to swap them out and use the power meter to find the most reflective mirror. Most of the ones we found were for the incorrect wavelength or severely damaged. With Peter's assistance and some closer inspection we found out that the original mirror was polarizing and this was the reason for the low power readings. With some rotation of that mirror we were able to get a better power reading and decided to leave it as none of the possible replacements were more reflective.

       Last week I finished reading three papers, two of which I presented at last weeks group meeting. The first compared nanoparticles produced from a bulk target and a wire irradiated end on. The second was about how the number of papers containing "laser" and "nanoparticle" has dramatically increased in the past few years. I was most interested in the search terms that are detailed in the paper. These should help me find more and better papers the next time I search. That paper also had a list of the most cited works that I think I should look through. The third paper that I read was about getting Silver nanoparticles in amorphous Carbon and Aluminum Nitride. They used Pulsed Laser Deposition to make their nanocomposites. I do not find this very relevant to me as there is not much about making nanoparticles but I think that Casey should read it as it seems to be quite relevant to his research.

More Reading

Today I hope to get through two papers. The first is about what effect target size has on alpha-Fe nanoparticle production using a pulsed laser. The second is about the structure and impact of literature, based on my cursory scan of the paper it has some search terms that should help me find more relevant papers in future searches.

Yesterday I continued researching nanoparticle production. The paper was about ZnO producing laser like emissions after being excited with 150ps pulse at 355nm. While it was an intersting paper it turned out to not have much to do with production of nanoparticles.

Lab visits

     Today I met with Ryan to learn more about LabVIEW. After some exploring I realized that LabVIEW is an expanded version of a program that I am very familiar with, Multimedia Logic. LabVIEW has more features and simple work is a bit more streamlined that is Multimedia Logic. It should be an easy transition should I start using it for research.
     After perusing LabVIEW I continued with reading papers the papers that I found last week. I found a most interesting paper about making metal and ceramic colloids in water and acetone. It describes how variables effects the nanoparticle production rate. From what I have read so far this paper is most relevant to what Steve has asked me to look into.
     Next I will continue with my research into the manufacture of nanoparticles and try to meet with Ryan and Kristen when they are doing lab work.

     Yesterday I met with Ryan in VanVlack. There he showed me some of the basics of taking pictures using the optical microscopes there. I learned how to add the scale bars to a picture and save the pictures to the flash card. It was also good to refresh my microscope skills. I would like to ask or find out how to save the pictures using FTP instead of saving them to flash and having to hook the flash up to a computer to get the images.
     After getting the needed picures we went to the laser lab in Gerstacker. Ryan breifly showed me the laser setup then we irradiated one of his samples. He introduced me to LabVIEW and the programs that he uses to control the movement of the sample.

Reading Papers

This weekend I read some of the papers that I found last week. I focused mainly on the experimental setups detailed in the papers so that I have some idea about what to expect in our lab. However, in order to understand the papers that I found I have needed to expand my laser related vocabulary. New words should also increase my understanding at the weekly meetings.

Lasers and nanoparticles

I am continuing to look for papers that pertain to the manufacture of nanoparticles and general information about how short pulse lasers interact with thin material films.
If Kristen or Ryan are available this weekend I will ask one of them to assess the relevance and credibility of some papers that I found. That would help me to focus future searches and be more discerning when I do so.