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Developing a picoammeter

  1. Jun 4, 2010 #1
    Hey,

    I'm interning at a lab that's in the midst of developing a picoammeter (a current measurement instrument capable of measure picoamperes). I'm a math major, not a physicist or an electrical engineer, so I don't haven't deeply studied electricity or its applications. I'm trying to gain an understanding of what types of things would produce currents in the picoampere range (I'm compiling a list). Also, what industries and fields of academia use picoammeters (e.g. semiconductor, nanotech)?

    Your answers are much appreciated. I want to do some research into these industries and fields, but I'm not quite sure where to look.

    Thank you,

    Mike
     
  2. jcsd
  3. Jun 4, 2010 #2

    berkeman

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    Staff: Mentor

    Re: Picoammeters

    I've only used them for one project, where we were trying to figure out what was causing dendritic growth across the PC board of one of our products many years ago. As the copper dendrites started to form, you could sense very small changes in resistance between the traces that had the bias voltage driving the growth.

    info on dendritic growth: http://www.ami.ac.uk/courses/topics/0152_caf/index.html [Broken]

    .
     
    Last edited by a moderator: May 4, 2017
  4. Jun 4, 2010 #3

    Borek

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    Staff: Mentor

    Re: Picoammeters

    In electrochemistry - voltammetry at microelectrodes. Especially fast voltammetry on microelectrodes with the radius measured in nanometers. Current can be very small and change fast (say from -pA to pA in less than ms). At least these were conditions we were thinking about around 1990, I wouldn't be surprised if at the moment they can be down to fA and μs.
     
  5. Jun 4, 2010 #4
    Re: Picoammeters

    In nanotech, they are used in scanning tunneling microscopes which measure leakage current that escaped from a potential barrier developed between electrodes and a sample in order to reconstruct an image.
     
  6. Jun 8, 2010 #5
    Re: Picoammeters

    Thanks a lot for your answers, this has been very helpful so far.
     
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