Melinda Chen

Update 0

Accomplishments

• Read through sputtering documentation and project primers

• Read through required textbook chapters and 'Filling in the Gaps' resources

• Met with project partner Katie to go through project goals and potential avenues forward

• Walked through state of current sputter chamber with team leads

Roadblocks

• No major blocks so far

Plans

• Literature review of current characterization techniques

• Meet with Katie to draft project proposal and timeline

Update 1 (1/19-1/26)

Accomplishments

• Drafted project proposal and timeline

• Researched thin film characterization techniques

• Submitted requests for training on XRR (with Professor Sokalski) and AFM

• Compiled existing sputtering chamber setups from online sources into spreadsheet

• Performed sputtering trials using Aluminum target + practiced tuning pressure using Argon flow rate and vacuum strength to maintain stable plasma

Roadblocks

• Priority is figuring out why the sputtering current is so low + how to tune sputtering parameters to improve power

Plans

• Get trained on XRR next Thursday

• Continue literature review

• Sputtering trials with Aluminum target --> Try sparking using high flow rate to create dense plasma then lowering pressure to increase amount of sputtered particles that reach the substrate

Responses

• From Jay

  • For the progress update, be sure to link to the document(s) that show evidence of your progress. this week that would be a link to you project proposal

    For roadblocks, this is an opportunity to request help, or clarify what you need from us to keep moving forward. I would argue training on certain equipment to be roadblock for you.

    For plans, there should be more detail in how you're going to proceed, or link to your working doc that demonstrates your plans in more detail. For example, link what literature you plan to read first, this helps me guide your research. What do you want to learn form theses trials? why is it useful in working towards the end goal. For example you could discuss the methodology for DC al sputtering and how that informs the development of reactive DC AL2O3 sputtering. Being specific helps me evaluate if your plans for the week will actually end up being productive. Based on Fridays session, ik that you have more specific well justified plans, so be sure to articulate them here, or better yet, direct me to a document that articulates your plans.

Update 2 (1/20-2/2)

Accomplishments

• Met with Professor Sokalski to discuss XRR

• Assisted chamber modifications for RF sputtering

• RF Sputtering trial with Aluminum target

  • learned how to use RF sputtering equipment and fundamentals behind impedance matching

• Chamber bias literature review

• Completed AFM online training and reached out to MCF contact for in-person training

Roadblocks

• Main roadblock is still sputtering chamber not working - will continue to look into specific reasons why target seems completely unscathed after a few hours of being near plasma

• Some of the RF sputtering electronics are cooked

Plans

• AFM in-person training

• Continue sputtering chamber debugging - both literature review and in-person tests

• Ideally also XRR in-person training, depends on how fast MCF contact responds.

Responses

• make sure to link working notes, and updated project tracker

• Good job finalizing choice of XRR for characterization

Update 3 (2/2-2/9)

Accomplishments

• Completed XRR training with Besty

• Completed AFM training

• Contacted Andrew to ask about correct AFM tips

• Helped perform sputtering tests on Thursday and Saturday to try to debug chamber

Roadblocks

• Sputtering chamber still not working - blocking capacitor seems like promising solution

Plans

• Perform sputtering test with Aluminum Oxide/Insulating material to test blocking capacitor theory

• Perform XRR on sample similar to expected sputtering chamber output

• Start writing SOPs + Drawing out schematic of characterization pipeline

Responses

• From Jay

  • Good job completing both AFM and XRR training, good job helping with sputter chamber debugging.

  • As discussed in person, RF sputtering test wont be fruitful until we implement a blocking capacitor. So I would prioritize XRR practice on oxide and evaporated Al samples.

  • Based on: https://www.lesker.com/newweb/ped/rateuniformity.cfm I worry that the oxide sputter test (hoping oxide acts a blocking cap itself) may not be a good use of time, since we may have to sputter for ridiculous amounts of time to see anything). Which is also another good reason to do Reactive Al Rf sputtering instead of Al2O3 target sputtering.

  • DC Al sputter tests may still be interesting this week.

  • Please make sure to links to working docs, and an updated github project tracker.

Update 4 (2/9-2/16)

Accomplishments

• Created Aluminum thin layer samples using the thermal evaporation chamber

• Attempted XRR on samples

  • Seemed to be unsuccessful - potentially issues with surface roughness, or sample size.

• Helped perform sputtering tests on Thursday with the blocking capacitor to try to debug chamber

• Placed order for AFM tips - turns out Joel has some

Roadblocks

• Sputtering chamber still not working : (

Plans

• Perform XRR on thermally grown oxide -> hopefully better surface roughness and larger sample size will result in visible results

• Track down AFM tips and try to perform AFM on thermally evaporated Al samples to get rough idea of surface roughness

• Continue literature review/researching potential causes for sputtering chamber not working.

Updated Project Tracker: https://github.com/orgs/hacker-fab/projects/36

Responses - Jay

• Given the chamber roadblocks, I think continuing to workout XRR with thermal oxide and sanity checking the evaporated Al samples with AFM techniques makes sense.

• Rahim and I are working on upping the Vp-p of th rf supply in hopes that low Vp-p has been the issue. If this doesnt work, we will start doing reactive DC with V1 chamber.