A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films (a process referred to as deposition) is a fundamental step in many applications. A familiar example is the household mirror, which typically has a thin metal coating on the back of a sheet of glass to form a reflective interface. The process of silvering was once commonly used to produce mirrors, while more recently the metal layer is deposited using techniques such as sputtering. Advances in thin film deposition techniques during the 20th century have enabled a wide range of technological breakthroughs in areas such as magnetic recording media, electronic semiconductor devices, Integrated passive devices, LEDs, optical coatings (such as antireflective coatings), hard coatings on cutting tools, and for both energy generation (e.g. thin-film solar cells) and storage (thin-film batteries). It is also being applied to pharmaceuticals, via thin-film drug delivery. A stack of thin films is called a multilayer.
In addition to their applied interest, thin films play an important role in the development and study of materials with new and unique properties. Examples include multiferroic materials, and superlattices that allow the study of quantum phenomena.
Hello everyone. My task is to select a thin film and deposition method that will achieve a few goals.
The thin film will be sandwitched between a diamond and nickel alloy. The thin film needs to:
Adhere to a diamond and nickel alloy strongly without inter diffusion.
Stay together up...
In optoelectronics and other nanotechnology applications (like organic photovoltaics, organic LEDs etc) most layers need to be electrically characterized among other types of measurements. Thus, sheet resistance is measured.
An example are the 4-point-probe resistivity measurements. Yet, what...
Homework Statement
In optics, the following expression needs to be evaluated in calculating the intensity
of light transmitted through a film after multiple reflections at the surfaces of the
film:
{\sum _{ n=0 }^{ \infty }{ { r }^{ 2n } } cos\quad n\theta })^{ 2 }+{ \sum _{ n=0 }^{ \infty...
Homework Statement
Consider steady, incompressible, parallel, laminar flow of a film of oil falling down an infinite vertical wall (Figure P-1). The oil film thickness is “h” and gravity acts in the negative Z-direction (downward on the figure). There is no applied pressure driving the flow –...
Homework Statement
Light of wavelength 550 nm in air is normally incident on a glass plate (n=1.5) whose thickness is 1.1 X 10^-5 m. (a) What is the thickness of the glass expressed in terms of the wavelength of light in glass?(b) How many reflected waves will experience the 180 degree phase...
Homework Statement
Plan plates of glass are in contact along one side and held apart by a wire 0.05 mm in diameter, parallel to the edge in contact and 20 cm distant. Using filtered green mercury light (λ = 546 nm), directed normally on the air film between plates, interference fringes are...
I have the XRD image of a PZT thin film. While trying to analyze it with JADE software I can not find the proper space group.So it is not giving me the answer I am looking for. I assumed the crystal system to be cubic.
Hi Everyone,
I am currently doing my final year in B.Tech Engineering Physics. During these 3 years studying this course, I understood that learning Engineering was never the intent of this course in my college.. Faculty were stuffing us with Pure Physics with Applied or Engineering Physics...
1. A thin film of oil (no = 1.50) with varying thickness floats on water (nw = 1.33). When it is illuminated from above by white light, the reflected colors are as shown in the figure. In air, the wavelength of yellow light is 580 nm.
a. Why are there no reflected colors at point A?
b. What is...
Homework Statement
A broad beam of light, of wavelength 683nm is sent directly down through the top plate of a pair of glass plates. The plates are 120mm long, touch at the left end and are separated by a wire of a diameter .048mm at the right end. Air between the plates act as a thin film...
Trying to get my head around constructive/destructive interference in thin film optics. The book does a good job of throwing formulas at you but I want some intuition.
If we shine a laser with λ = 600 nm on a thin film of a material with refractive index 1.5, at what thicknesses will we get...
Hi everyone,
I need a coating material for an moving object. The coating surface slide over another surface. The coating needs to be transparent to allow optics tracking, and flexible like paper because inner object is flexible, and it needs to be wear resistant to keep the transparent...
How do i demonstrate thin film interference with microscope slides?
Textbook questions all mention that you will get parallel fringes when you put a hair between two microscope slides.
However, i have tried doing so, but don't get the parallel fringes. I used a red laser pointer, and a...
Homework Statement
A lens (##\mu##=1.5) is coated with a thin film of refractive index 1.2 in order to reduce the reflection from the surface at ##\lambda=480 nm##. Find the minimum thickness of the film which will minimize the intensity of reflected. [Assume near normal incidence]Homework...
I'm working for the Company that specialize in thin film polyethylene. I research the tendency of using biodegradable thin film for packaging, Anyone that have knowledge or information about this such as report of the kinds of polymer used in that field. Please give me a help.
thanks a lot
Thin Film Interference Problem: A hair is placed at the edge...
Homework Statement
Thin Film Interference Problem: A hair is placed at the edge between two 10.0 cm glass plates of n= 1.52.
Light of 400 nm wavelength shines on the glass and an interference pattern is formed. If the...
Hello,
I want to ask how can one calculate the thickness of a thin film (or each of the thin films in a stack of 3-4 thin films on one another) when
- complex refractive index of each thin film is known (n and k). This refractive index is obtained from a single wavelength ellipsometer and...
Homework Statement
Light strikes two plane sheets of glass with a thin air space between them as shown. If the light has a wavelength of 580 nm and the air space between the glass has a thickness of 870 nm, predict whether the reflected light as demonstrated by rays A and B will cancel or...
Homework Statement
A scientist notices that an oil slick floating on water when viewed from above has many different rainbow colors reflecting off the surface. She aims a spectrometer at a particular spot and measures the wavelength to be 750 {\rm nm} (in air). The index of refraction of...
How does the efficiency of a Thin Film solar cell compare to the efficiency of a single crystal solar cell with reference to the 5 main solar cell parameters ( Iopt , Rs, Rsh, Is and n )?
I know series resistance( Rs ) will probably increase in thin film cells because of grain boundaries...
I have been reading recently on the properties of evaporated thin film bismuth, particularly grain size and resistivity. Usually evaporated bismuth is amorphous and semimetallic, with very small grain size. Grain size can be increased and resistance lowered by annealing the film. It has been...
Homework Statement
White light is sent downward onto a horizontal thin film that is sandwiched between two materials. The indexes of refraction are 1.80 for the top material, 1.68 for the thin film, and 1.50 for the bottom material. The film thickness is 5.24*10^-7 m.
(a) Of the visible...
Hi all,
I'm studying for the GRE test and I have noticed that sometimes questions about thin film appear.
Is there any reference where I can learn some basical knowledge about thin film reflection and refraction? I'm not looking for something deep. Just a general overview.
Thanks
Hi guys. I am new to this forum and need some help in solving some problems.
My company produce thin film heater( doped tin oxide deposited on a substrate such as glass ceramic, beryllium oxide, aluminium nitride or alumina and some others). I need a formula for calculating within a few degrees...
Hello,
I'm reading something about adsorbate induced surface resistivity changes in thin metal films
and there is often mentioning of electron-hole pair damping, as for example:
"electron-hole pair damping of the parallel(to the surface of thin film) frustrated vibration of the...
Thin film diffraction -- need help to start
Homework Statement
I attached a picture of the problem, could anyone tell how I would begin to proceed with this problem? I believe that it is more complicated than simply a Snell's law problem, due to the thin film of oil.
Thanks for your...
Homework Statement
33. This experiment projects a red laser light beam of wavelength λ through a diffraction grating labeled 750 lines/mm onto a screen that is positioned a distance l from the diffraction grating. The diffraction grating has a distance d between adjacent lines. The...
Homework Statement
A sheet of glass having an index of refraction of 1.20 is to be coated with a film of material having an index of refraction of 1.42 such that green light with a wavelength of 525 nm (in air) is preferentially transmitted via constructive interference.
What is the minimum...
Homework Statement
Two rectangular plates (n = 1.60) are in contact along one edge and separated along the opposite edge (see figure). Light with a wavelength of 600 nm is incident perpendicularly onto the top plate. The air between the plates acts as a thin film. Nine dark fringes and eight...
Homework Statement
A thin layer of water (n=1.33) is surrounded by air what wavelength of light will not be transmitted through the water at the point where the water is 113 nm thick?
The Attempt at a Solution
- In phase
- Path difference of 2T.
- Constructive Interference
I just...
Hello, I am having some difficulties understanding this concept. It seems like wikipedia and my notes/teacher contradict each other
According to my equation sheet, the equation for dark spots is 2nt = mλ and for bright spots is 2nt = (m + 0.5)λ. However, if a phase shift of 180 degrees occurs...
Hallo alle users,
as the title indicates, I have a question about measurement of thin film thickness by means of spectral reflectance.
Given, the to be measured thin film has thickness less than 600 nm, but the measuring light has only wavelengh larger than 600 nm. Does it mean, that the...
Hi guys, long time reader new poster.
I am looking for ways to determine the thickness of some thin films of zinc oxide I have been producing. Conventionally I use SEM cross section, but the throughput of films has made this a little taxing. I've tried also weighing the substrates before...
Homework Statement
A very thin sheet of plastic (n=1.70) covers one slit of a double-slit apparatus illuminated by 630 nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?
Homework Equations
Constructive...
Homework Statement
A thin film of alcohol (n=1.36) lies on a flat glass plate (n=1.51). When monochromatic light whose wavelength can be changed, is incident normally, the reflected light is minimum for λ=512 nm and a maximum for λ=640 nm. What is the thickness of the film?
Homework...
I put together this little movie as (hopefully) the first in a series.
http://www.youtube.com/watch?v=xjMjWtntm9k"
My target audience is a second semester class of physics students that have already had a lectures in basic wave optics. When I give this URL to my students, it's with the...
Look at the picture below, I have to prove that the optical path length difference is
\Delta=n(BC+CD)-BE=2nd\cos(r)
[PLAIN]http://img200.imageshack.us/img200/2271/schermata082455775alle1.th.png
The problem is just how to get 2nd\cos(r)
I actually don't have any idea :\
I have...
Hello, I am trying to understand thin film (in air) interference but I have a problem:
I know we have destructive interference when \delta=(2m+1)\pi.
Now i can try to calculate the thickness of the film to get it, so
since \delta =\frac{4nt\pi}{\lambda} - \pi where t is the thickness...
Homework Statement
A piece of paper of thickness 15 * 10^-6 m is used to create an air wedge between 2 glass slides that are 7.25 cm long. If the wavelength of the light being used is 595 nm, how many interference fringes are counted across the entire pattern?
Homework Equations
delta...
1. Calculate the minimum thickness of the film for which the intensity of the reflected red ray is near zero.
(This is AP Physics B 2010 (c)ii.)
I found the wavelength in the film to be 4.81x10-7 m
nf=1.382. 2L=mλ (destructive interference)
The Attempt at a Solution
My first attempt yielded a...
Homework Statement
A pair of very flat glass plates, 7.41 cm long, touch at one end and are separated at the other end by a small piece of 44 gauge copper wire, 5.08×10−5 m in diameter. An air wedge is formed between the glass plates by this supporting wire. Light of wavelength 631 nm...
I am looking over thin film interference and am having some difficulty understanding when to know if a reflected ray will be 180 degrees out of phase or in phase. I know that a ray reflecting off a medium with a higher index of refraction will have a 180 degree phase change; and that a ray...
Homework Statement
See figure attached.
Homework Equations
The Attempt at a Solution
Not too sure how to do this one.
I tried thinking about what it was doing before the air was replaced with the liquid.
With air,
The first reflection would have no phase shift (glass...
Homework Statement
White light is sent downward onto a horizontal thin film that is sandwiched between two materials. The indexes of refraction are 1.80 for the top material, 1.66 for the thin film, and 1.50 for the bottom material. The film thickness is 5.4 10-7 m.
Homework...
HELP with thin film problem!
Homework Statement
Consider a horizontal plane of thin film with
a thickness t. This film is located in between
air and water (see sketch). Light is directed
from the air downward through the film and
into the water, perpendicular to the surfaces.The index...
Homework Statement
So I have a similar situation with the traditional Newton rings. Instead of having however a convex lens, I have a (partial) spherical surface with height d with sitting on top of a thin film of thickness t, with d >>> t, and refractive index n and below the thin film is a...
Hello everyone. I need to simulate flux densities generated by thin films of permanent magnets of varying composition. This is to guide selection of parameters for sputtering of Nd-Fe-B permanent magnets. Does anyone know of a program which will allow me to simulate fields from permanent...
Homework Statement
Light of wavelength 526 nm is incident normally on a film of water 1.0 µm thick. The index of refraction of water is 1.33.
(c) What is the phase difference between the wave reflected from the top of the air-water interface and the one reflected from the bottom of the...
Hello there,
Right now I'm in a physics lab in which I have a vacuum jar, a thin film evaporation apparatus, and the instructions to do something interesting. I'm looking at a bunch of ideas right now, but one project that appeals to me is a multi-layer anti-reflective coating. The way I'd...
Homework Statement
I need to calculate n, k and d of an "unknown" thin film.
I have the transmission spectra of the substrate (MgF2) and substrate + "unknown" thin film
See the attachments with: three files
- two screenshots of the transmission spectra (see file name for description)
-...