1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: A few questions on Nanotechnology (Microscopes/Optics)

  1. May 15, 2012 #1
    I've been going through some past papers in preparation for my exam tomorrow. We have not been given the past paper answers so i was wondering if anyone could help me with some of the answers. I will post multiple questions here but help with any of them would be greatly apprechiated

    The problem statement, all variables and given/known data
    A microscope equipped with an oil filled objective lens with a numerical aperture of 1.2 is used to
    image the patterned features on a semiconductor substrate. Define what is meant by the numerical
    aperture and explain why the lens is oil filled. Using the Rayleigh Criteria, define the smallest
    resolvable features when light of wavelength 633 nm is used to illuminate the substrate and the oil
    filled objective is use

    The attempt at a solution
    Numerical Aperture is a numerical value which indicates the range of angles at which a system can accept/emit light

    I know d = (0.61[Lambda]) / 2nsinu
    and NA is nsinu.

    Therefore d = (0.61*633*10^-9)/2.4

    Is this correct? and why is the lens oil filled?

    The problem statement, all variables and given/known data

    A tube scanner made of a PZT piezoceramic material, which has a piezoelectric coefficient, d31=-
    , has a length of 12.5 mm and wall thickness of 0.5 mm. Calculate the ratio of
    displacement dz per unit volt. How could elevated temperatures affect the piezoceramic material?

    The attempt at a solution

    Using a formula i can show that dz/U = L / h d(31) = 12.5*10^-3 / 0.27*10-12 * 0.5*10^-3

    Is that correct for the displacement dz per unit volt, and how does elevated temperatures effect the materiel?
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted