Month: June 2020

MFF Equipment Status

Instrument Status Status Notes
6″ Sputter deposition  Ready Air leak on the gate valve pneumatic cylinder

Cr – 100 W 10 nm/min Load: 3.49 Tune: 1.66
Au – 100 W 30 nm/min Load: 4.0 Tune: 1.46
Al – 100 W 20 nm/min Load: 4.83 Tune: 0.44
SiO2 – 100 W 5 nm/min Load:  Tune:

8″ Sputter deposition Ready Issues – Need to fix the hoist or take weight off the system
Denton e-beam deposition  Ready
Fredrick e-beam deposition  Unavailable Cryo pump and compressor needs a rebuild
Parylene Coater  Ready
TRION  Ready Rough pump needs to be rebuild, but it is operational with the CAIBE rough pump which gives a better vacuum
CAIBE  Unavailable Need to test with water cold stage and determine the beam current
March  Ready Cleaning: 200 W, 100 sccm O2, 300 secs
PDMS bonding:
40-50 W (maybe hard to get reflective power below 10 W), 100 sccm O2, 60 secs, after plasma treatment place the PDMS and glass together and heat treat at 80oC for 60 mins
Stripping carbonized SU-8: 300 W, 100 sccm O2, 300 secs (may take longer, depending on thickness)
Ellipsometer  Ready
FTIR  Ready Issues – Calibration
Curvature System  Ready Issues – Calibration
Oxidation Furnace  Ready
Diffusion Furnace  Ready
2″ Furnace  Ready
RTP  Unavailable TC wafer needs replacing and spot welded onto the connectors
EasyNano CVD CNT Ready Issue: Need to replace the pressure switch in the gas cabinet as it is flaky
Dicing Saw  Ready
EV620 Mask Aligner  Ready Turning off the lamp to preserve the life timeIssues – Logging sometimes fails as the optics stage gets stuck, the y motor also losses firmware if system is off too long
Wet bench – Chemical processing  Ready
Vacuum oven  Ready
Hotplates  Ready
Spinner  Ready
Wire bonder  Ready
Filmertics 3D Profiler Ready
Cleanroom Optical Microscopy  Ready Issues – Calibrate the CCD capture measurements
Probe station  Ready Issues – Need to install new probes from eBay
4200A – SCS Parameter Analyzer  Ready
Four point conductivity  Unavailable
Atomic Layer Deposition Ready 20190401 – New TDMAH installed and Hf deposition tuned to give a 4″ uniform deposition, growth rate is too fast per cycle, need to calibrate for the ALD region

20181205 – Milled a trench in the sleeve, put in the old ceramic pins, put in metal pins to stop the sleeve from moving

20181015 – Redo the N2 to be SS instead of plastic

201805023 – set up the process to represent an ALD valve that has constant Ar carrier flow

20180601 – Installed Ferrocene iron ALD source

20180814 – changed the precursor setup – Ferrocene is not producing a vapor pressure?

20190102 – Replaced the manual shut off valve on the ferrocene with an all metal valve – finally do not see F – not sure if it was the valve. Disconnected all the lines to the shower head that is not used.

20190219 – Installed the TDMAH to test uniformity and optimize the system

Big blue wet benches Useable 20181015 – Connected the 3-phase supply to the left side
Connected the aspirator, ran a new waste line to the current acid neutralization system. Need to install an automatic water shut off valve to the house water as the shut off requires a 10′ ladder to get to.

New Approach to Simultaneous In Situ Measurements of the Air/Liquid/Solid Interface Using PM-IRRAS

Chathura de Alwis1, Timothy R. Leftwich2, Kathryn A. Perrine1,*

1 – Department of Chemistry, Michigan Technological University, Houghton, MI 49931

2 – Department of Material Science & Engineering, Michigan Technological University, Houghton, MI 49931

*corresponding author; kaperrin@mtu.edu

Abstract

Abstract Image

Vibrational spectroscopy techniques have evolved to measure gases, liquids, and solids at surfaces and interfaces. In the field of surface-sensitive vibrational spectroscopy, infrared spectroscopy measures the adsorption on surfaces and changes from reactions. Previous polarized modulated-infrared reflection–absorption spectroscopy (PM-IRRAS) measurements at the gas/solid interface were developed to observe catalytic reactions near reaction conditions. Other PM-IRRAS measurements use liquid cells where the sample is submerged and compressed against a prism that has traditionally been used for electrochemical reactions. This article presents a new method that is used to observe in situ adsorption of molecules using PM-IRRAS at the gas/liquid/solid interface. We demonstrate the meniscus method by measuring the adsorption of octadecanethiol on gold surfaces. Characterization of self-assembled monolayers (SAMs), the “gold standard” for PM-IRRAS calibration measurements, was measured in ethanol solutions. The condensed-phase (air/liquid) interface in addition to the liquid/solid interface was measured simultaneously in solution. These are compared with liquid attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy measurements to confirm the presence of the SAM and liquid ethanol. A model of the three-phase system is used to approximate the thickness of the liquid ethanol layer and correlate these values to signal attenuation using PM-IRRAS. This proof-of-concept study enables the measurement of reactions at the gas/liquid/solid interface that could be adapted for other reactions at the electrode and electrolyte interfaces with applications in environmental science and heterogeneous catalysis.

Au/Cr coated glass slides produced using the 6″ Sputtering system in the Microfabrication Facility

de Alwis, C., Leftwich, T.R. and Perrine, K.A., 2020. New Approach to Simultaneous In Situ Measurements of the Air/Liquid/Solid Interface Using PM-IRRAS. Langmuir, 36(13), pp.3404-3414.


Magneto-optics of subwavelength all-dielectric gratings

ANDREY A. VORONOV,1,2,* DOLENDRA KARKI,3 DARIA O. IGNATYEVA,1,2 MIKHAIL A. KOZHAEV,2,4 MIGUEL LEVY,3 AND VLADIMIR I. BELOTELOV1,2

1- Faculty of Physics, Lomonosov Moscow State University, Leninskie Gory, 1-2, Moscow 119991, Russia
2 – Russian Quantum Center, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russia
3 – Physics Department, Michigan Technological University, Houghton, MI 49931, USA
4 – Prokhorov General Physics Institute of the Russian Academy of Science, 38 Vavilov Street, Moscow 119991, Russia 

We provide the experimental research on a novel type of all-dielectric magnetic structure designed to achieve an enhanced magneto-optical response. 1D grating fabricated via etching of bismuth substituted iron garnet film supports the excitation of optical guided modes, which are highly sensitive to the external magnetic field. A unique feature of proposed structure is the synergetic combination of high transparency, tunability, high Q-factor of the resonances and superior magneto-optical response that is two orders higher in magnitude than in the non-structured smooth iron-garnet film. The considered all-dielectric magnetic garnet structures have great potential in various fields including the magneto-optical modulation of light, biosensing and magnetometry.

Voronov, A.A., Karki, D., Ignatyeva, D.O., Kozhaev, M.A., Levy, M. and Belotelov, V.I., 2020. Magneto-optics of subwavelength all-dielectric gratings. Optics Express, 28(12), pp.17988-17996.