Nanoscale Thin Films
Nanoscale Thin Films
Our sponsorNSF award # 0531171Center for Hierarchical ManufacturingUniversity of Massachusetts Amherst
Today’s Agenda Ben Franklin’s Observation Interactions between Oleic Acid andWater Create a thin film of oleic acid Calculate the thickness of the thin filmof oleic acid
Was Ben Franklin an Early Nanoscientist?
Excerpt from Letter of Benjamin Franklin to William Brownrigg (Nov. 7, 1773).At length being at Clapham, where there is, on the Common, a largePond . I fetched out a Cruet of Oil, and dropt a little of it on the Water. Isaw it spread itself with surprising Swiftness upon the Surface . the Oiltho' not more than a Tea Spoonful . which spread amazingly, andextended itself gradually till it reached the Lee Side, making all thatQuarter of the Pond, perhaps half an Acre, as smooth as a LookingGlass.
. the Oil tho' not more than a Tea Spoonful . perhaps half an AcreCHALLENGE: How thick was the film of Ben Franklin’s oil?Volume (Area)(Thickness)V ATT V/AV 1 teaspoonfulA 0.5 acre 2cm3 2,000 m220,000,000 cm2T 2 cm320,000,000 cm2T 0.0000001 cmT 1 x 10-7 cmT 1 x 10-9 mT 1 nanometer
It would be difficult to conduct a thin filmexperiment on the UMass Amherstcampus pond.
A plastic tray can be used toexperiment with thin films.However, you need to use much lessthan a teaspoon of oil.
You will form a thin film on the surface ofwater using a small amount of one ofolive oil’s ingredients.
That ingredient is oleic acid.
There is an attraction between the polarend of oleic acid molecules and polarwater molecules.
When you pour a very small amount of oleic acidonto the surface of water, the oleic acid molecules can“self-assemble” into a thin layer.
In a small drop of oleic acid there are billionsof oleic acid molecules that will stand up likeblades of grass on the surface of water.water
The thin film of oleic acid forms a LangmuirFilm. The thin film can be confined to a specificarea with a barrier. You will use small particlesas a confining barrier.hydrophobic endwaterhydrophilic end
Now its your turn to create a thinlayer on the surface of water. Water is in each plastic tray. Make a very dilute solution of oleic acid in alcohol. Determine how many drops of a very dilute solutionare in one cm3 of the very dilute solution. Evenly sprinkle a layer of baby powder across thesurface of the water. Let one drop of the very dilute solution of oleic acidspread across the surface of the water. The alcohol solvent will dissolve in water leaving athin film of oleic acid solute on the surface Measure the average diameter of the circular layer ofoleic acid.
Nanoscale Calculations The procedure and calculationworksheets are provided. One side of the worksheet includeshints for calculations. Calculators need to be shared.
A Sample Calculation of the volume ofoleic acid in just one drop of the seconddilute solutionThe following steps correspond to the sequence ofcalculations on your calculation worksheet.Step 1: The volume fraction 1 / 25Step 2: 0.04 cm3Step 3: 0.04 cm3 / 25 0.0016 cm3Step 4: A group determined that 40 drops of the seconddilute solution 1.0 cm3.Step 5: If a group determined that 40 drops of the secondsolution of oleic acid had a volume of 1.0 cm3; Then0.0016 cm3 / 40 0.00004 cm3.
A sample calculation of thethickness of the oleic acid filmStep 6: If a group estimated that average diameter theirthin film of oleic acid was 14.50 cm, then the averageradius is 7.25 cm.Step 7: Area 3.14 x R2 For example: The area of thatthin film was 165.05 cm2Step 8: If Volume Area x Depth; Then: Depth Volume / Area and the thickness of theexample group’s film would be 2.42 x 10-7 cm.Step 9: 2.42 x 10-7 cm 2.42 x 10-9 m 2.42 nanometers
Big Ideas in Self-Assembly Mobile structural componentsTarget is low energy equilibrium stateOrdered structuresAssembly through attraction or repulsionforces between the componentsEnvironment selected to induce designedinteractionComponents retain physical identitythrough and afterReversible by controlling the environmentWhitesides & Boncheva (2002)
A Few QuestionsWhat might be some sources of errorwhen calculating the thickness of alayer of oleic acid?How could the sources of error beminimized?How might you integrate this activityinto a STEM curriculum?
Excerpt from Letter of Benjamin Franklin to William Brownrigg (Excerpt from Letter of Benjamin Franklin to William Brownrigg (Nov. 7, 1773) .At length being at Clapham, where there is, on the Common, a .At length being at Clapham, where there is, on the Common, a large Pond . I fetche
Optoelectronic properties of the obtained thin films were measured using UV-Vis spectroscopy (UV-3101PC). A 4-probe Keithley 2400 source meter was used to obtain the I-V characteristics and electrical resistance of the films. Results and discussion: Figure 1 shows XRD patterns of the as-deposited and annealed InBiS 3 thin films. The as-
electronic structure in amorphous oxide semiconductor, a-InGaZnO4," Thin Solid Films 486(1-2), 38-41 (2005). 11. A. Suresh, P. Gollakota, P. Wellenius, A. Dhawan, and J. F. Muth, "Transparent, high mobility InGaZnO thin films deposited by PLD," Thin Solid Films 516(7), 1326-1329 (2008). #238523 Received 21 Apr 2015; revised 12 Jun .
The coefficient of thermal expansion CTE is an important mechanical property for thin film materials. There are several problems . that arise from the thermal expansion effect; for example, the mismatch of thermal expansion between the thin films and the underlying substrate may lead to residual stresses in the thin films.
zinc oxide thin films, possibly achieved without any post- growth treatment of the deposited ZnO layers [2]. Normally ZnO founds in the hexagonal structure [3]. ZnO thin films is interested as transparent conductor, because the n-type ZnO thin film has a wide band gap (E. g 3.2 eV), and high transmission in the visible range, and ZnO thin
The thin solid films were probably first obtained by electrolysis in 1838. Bunsen and Grove obtained metal films in 1852 by means of chemical reaction. Faraday obtained metal films in 1857 by thermal evaporation of metallic elements. Thin films are two dimensional solids. In these
Growth and Characterization of Conducting ZnO Thin Films . In addition, the various analytical data of the ZnO films were compared with those of ZnO single crystal. According to our analytical data, metallic zinc plays an important role for the high conductivity in ALD ZnO films. Therefore when the metallic zinc was additionally oxidized with .
Markus Böl · Stefanie Reese · Kevin Kit Parker . tural response of layered muscular sheets for cardiac repair. 2 Modeling of muscular thin films For the modeling of muscular thin films, we begin at the . by convergence considerations, see [9]. 2.2 The cardiac muscle fibers
Thin films of hafnium dioxide (HfO. 2) are used widely as the gate oxide in fabricating integrated circuits (ICs) because of their high dielectric constants. In this paper, we report the growth of thin films of hafnium dioxide (Hf
