MBE Upgrades

1. MBE Upgrades • What upgrades? • Change cell type to have a more narrow openning • QCM to determine Ti flux and quicker calib. • Why (in general) need to do these upgrades? • Better control of Sr, Ba & Ti fluxes • Too much variation from time shutter opens because of built up pressure • Why will these upgrades help me achieve growth of BTO dots? • More control of flues, the better I’m able to control formation of dots or influence their changes

2. MBE Upgrades Progress • New cells will not be changed until further growths of BTO dots • Why? • If we change cells now, we will delay possible discoveries now • Changing cells takes time; we have to vent chamber • Changing cells also implies changes in growth conditions and discovering them for the new setup takes time • Does this make sense to me? • Yes

3. MBE Upgrades Prep • Preparing for changing cells • Hooking up Eurotherm controllers: ordered, receieved, installed comm cards; wired all power and comm cables togther; successfully communicated with computer and updated some of thermocouple types • Learned to turn off power when wiring and working with devices • Learned that I always need to know specifics of devices – always do careful homework; it prevents frustration and losing time • Learned about patience in overcoming “trivial” challenges • Learned about frustrations in understanding standards

4. MBE Upgrades Prep • More about Eurotherm Controllers • Develop a tutorial on how to order and hookup a eurotherm controller and power supply • Why work on Eurotherm controllers now? • When cells are installed, all we have to do is hook them up to the cells rather than wait and delay • Lambda power supplies • Made power cords and ran neatly to avoid clutter • Learned about appropriate size wire for current drawing • Why use Lambda? – good reputation

5. MBE Upgrades Prep • Should we swap Veeco power supplies with Lambda power supplies? • I propose we do when we change out the cells • According to experience with Nitride group, Veeco power supplies fail; I would rather prevent power failure even if in requires a little more delay now • Because we will know how to hook up Eurotherm and Lambda power supplies with other six no problem • Should we get a La & Al cell? • Dr Chakhalian says that not possible to chemically etch LAO substrate to get atomically flat • Use to grow a buffer layer that will allow for BTO dots form

6. Substrate Prep • BTO Dot growth • MgO found paper • Started trying to replicate • LaAlO3  talked to Dr Chakhaliansinec I know his group has tried • Cannot prep chemically for atomic steps • TEM • STO  need to replicate Dr Chakhalian’s work • Why? – need to look at interface of homoepitaxy growth to get good experience in oxide cross sectional TEM • Had many problems when trying others

7. XPS • Why trying to use it? • Want to evaluate composition of surfaces and changes made to them for substrate preparation and determination of dot composition • Need to be able to differentiate between such things as SrO and TiO2 and STO • Not sure have a good plan of how to use it to evaluate surface • Have one paper that seems to use it, but don’t fully understand analysis • Develop expertise in capabilities • Need to do depth profiling tests

8. Proposal • Committee • Found Dr Ulrich to be on committee • Need to finalize Dr Bellaiche and Chakalian • Outline Development • Started using Project to help plan  it helps me think about things more easily • Have not spent time researching individual topics to come up with good ideas to propose • Why I have not progressed much farther? • I don’t break it down one step at a time and tackle it • Hard time balancing work and getting this done