Wednesday, August 7, 2013

MEMS Devices in the Classroom

In order to assemble all of the different activities that I composed this summer, I put all of the documents together in one website using Google Sites.

You can access the site by CLICKING HERE.  The goal of this site, is for teachers to access the resources and bring current micro-technologies into their classrooms.

Monday, July 29, 2013

Engineering Humor

Went to use the microwave for lunch, and found this clever play on words.

"Cover your food!! ...or use the other 'micro'wave"

Photolithography in the Clean Room

At Boston University's Photonics Center (PHO) there is a "Cleanroom" also known as the Optoelectronic Processing Facility (OPF).  OPF is a multi-user cleanroom, or a Shared Facility at BU, meaning that all of the equipment inside this lab is available for any faculty/staff member or student to use as long as they are trained or have the assistance of the laboratory manager, Mr. Paul Mak.  The cleanroom gets it's name because it's "so clean." The room has less particles in the air than any ordinary laboratory room, so if a researcher is examining a super small device/machine in the cleanroom, then there would be a less likely hood of a particle of dust in the air contaminating the device.  There are actually two cleanrooms at BU, one is the Class 1,000 Cleanroom and the other is
Helen Fawcett Outside
the Class 100 cleanroom. Which cleanroom do you think is "cleaner"? You'd be right, if you said that the Class 100 cleanroom is cleaner because the Class 100 cleanroom has less particles in the air that the Class 1,000 cleanroom. In the picture above and on the right, you will see (from Left to Right) Ben Fawcett (high school student), Jessica Leach (RET), and myself dressed up in funny-looking "bunny suits."  We need to wear these outfits in order to enter the cleanroom so that we do not bring in any unwanted particles from our hair, skin, clothes, shoes, or hands; we're also wearing safety goggles to protect our eyes from anything harmful inside the lab.  To the left, you'll see Helen Fawcett (Manager of Operations and Technical Programs and Primary Investigator of RET at BU) is standing outside the cleanroom.  The doors are sealed off and need to remain shut in order to maintain the Class 100 cleanroom.

Inside Class 100 cleanroom
  I was lucky enough to spend a day in the cleanroom using a process of Photolithography.  Using photolithography, I was able to create/print a design onto a clear transparency, which served as the mask which allows only certain areas to allow light to shine through.  After the mask was printed, we used the clean room to deposit and etch away the design onto a silicon wafer. In the photo to the right, you will see that I am placing a silicon wafer (looks like a small CD disk with out a hole in the center) onto the spinner.  I needed to use special tweezers to pick up and hold the silicon wafer on it's edge so that I didn't contaminate/dirty the silicon wafer with a fingerprint before we even started!

Miss Lagas' Mask
Pouring Photoresist
  To the left, you will see Paul Mak (laboratory manager) monitoring me as I poured the photoresist onto the silicon wafer, which is on the spinner; the spinner will spin the silicon wafer and as it does this, it forces the photoresist to spread out into a thin and even layer on the silicon wafer.  The photoresist kind of works like film in an old 35mm camera (before the ages of digital photography). The film inside the 35mm camera is exposed to light and the image that is being taken, with some areas having more or less light come through to the film.  During
Deposited Gold
photolithography, the photoresist is exposed to a certain amount of UV light and whatever part of the photoresist that is exposed to the UV light will get washed away. After photoresist is poured onto the silicon wafer then the wafer is placed under UV light, but the mask (the clear transparency with my design) is placed between the UV and the wafer so that only the blank areas of the design are exposed to the UV light.  Once the UV light exposure is complete, then gold (yes gold!) is deposited onto the silicon wafer and then the silicon wafer looks like a sheet of gold, until the wafer is placed in an acetone wash, which you can watch below!  Look for the finished product on Miss Lagas' desk when we're back at school!

Wednesday, July 24, 2013

My return to BU for RET round 2!

Three years ago I spent a summer at Boston University's Photonics Center working for a program called Research Experiences for Teachers (RET). The program is funded by the National Science Foundation (NSF) and is designed for middle and high school teachers to work in a research laboratory at a university in order to experience current research first hand, but also to bring the experience back to students in the classroom.  During my first year, I met and worked with a wonderful group of teachers during BU's first year of the RET program.  This year, I was asked back to work in a different laboratory with a new cohort of teachers.  I am one of five teachers working at BU this summer, three of the teachers participated last summer (2012), one teacher participated in the summer 2011 group, and I am representing the participants from 2010.

I'm very excited to be back at BU's Photonics Center for another yet another summer working in the lab!  Below are images from week 1.  This year we didn't waste any time getting started.  Since all of the teachers are returning to the program for year 2, we were able to jump right in head first.  I am assigned to Professor Bishop's Research Laboratory, where I will work on an outreach program for his lab.  Below are a few photos that I took during my first week on the job. 
Jackson and Han working in the Clean Room during the sacrificial release (HF wash) of their MEMS devices.  The sacrificial release removes the sacrificial layers that support and hold up the features of a MEMS device during fabrication (when the device is built).  FYI, HF stands for Hydrofluoric Acid and it's very dangerous!

Experimental set-up under the fume hood in the clean room where Jackson and Han are working on the sacrificial release.

Han completing the sacrificial release using the Critical Point Dryer in the Clean Room.

Wednesday, July 21, 2010

A Look Back at Week 3

Week 3 has come and gone! It's hard to believe this experience is half way over already. Lesson planning is well under way for how the teachers are going to implement our research experiences into the classroom.

This week, Helen took us to the clean room for the second time. I worked with Gary, John P. and Rick to make our wafers. (Kevin made the mask the week before when we were all in the clean room). It was a great experience because my partner John W. and I are actually using small wafers. also known as cells, in our laboratory (BSAIL). I won't be using the actual wafer that I made in the clean room, but it was neat learning the processes necessary to create the wafers used in our laboratory.

On Friday this week, John took me out to UMASS to check out his old bacteria laboratory that he worked in. It was a very interesting experience, because I was able to see another laboratory besides the engineering laboratories at Boston University. John seemed right at home in his old lab and very excited to share his past experiences working in the lab.

I'm looking forward to next week because hopefully John and I are going to get started using the IRIS system!

Do you know how to culture bacteria?

Monday, July 12, 2010

A Look Back... Week 2 Reflections.

What is the Hypothesis you are testing?
John and I are going to do research with an e-coli stand. We are going to test the e-coli against it's antibody, and see if they bind using the LED or Laser system. If time allows (normally research is ongoing and takes years), since we only have four weeks left, we may be able to compare our results of the Laser system against the LED system. The laser system will give more accurate results, but the LED system is what will eventually be affordable and taken into the field. Normally the BSAIL laboratory works with viral detection, but John and I proposed using the same system to detect bacteria (e-coli specifically). If we can successfully test the presence of bacteria at various quantities, then this system that is being developed to take into the field can be used as an environmental detector for water quality.

What kind of controls does the experiment have?
John and I are going to test the effectiveness of the IRIS system in detecting bacteria using possibly both the laser and LED systems. The laser system would be baseline data because it is more accurate and then we could compare our results using the LED system to our results from the laser system. Our first runs of the experiment may serve as a control to test other bacterial strains for binding. We have ordered a generic antibody for e-coli bacterial strains. Towards the end of our research if time allows we could run different bacterium against the antibody.

How will you measure your results?
We will measure our results using computer and graphical analysis of the images collected of the binding of the e-coli with the antibodies. The IRIS system is able to produce a visual image of binding as well as quantify.

How will the reliability of your data be ensured?
The reliability of our data will be ensured through repeated experimentation and the use of different equipment for bacterial detection. Alex, a graduate student here, works on the calibration of the laboratory equipment because one of his roles in the lab is to construct the equipment. We will need to run repeated experiments with varying concentrations to verify the data. Our data could potentially serve as (preliminary) baseline experimental data, which could one day be compared to results obtained in the field.

How will inquiry figure into your lesson plan?
I am looking forward to the challenge of implementing this experience into my curriculum. I think that a few of the concepts that I have been learning about this far will fit in nicely in my chemistry, biology, and ecology units. I will fit inquiry into my lesson planning by keeping in mind the curiosity and wonder that the students, may have for the individual project that I am working on.

What materials will you use to carry out your lesson
I hope that we will be able to bring a mask back to our classroom for our students to observe, I also hope to bring back images that were taken through out these six weeks to facilitate discussion and trigger questions. I would also like to use a laser and LED light simply to discuss the differences between the two and how they can be used as a biosensor.