Nanofabrication and Devices
(in ECE and ME Departments)
John Melngailis
Department of Electrical and Computer Engineering
&
Institute for Research in Engineering and Applied
Physics.
University of Maryland, College Park
Nanofabrication
- electron beam lithography, (SEM with beam writing
software, 20nm min. features) C.H. Yang
- focused ion beam, milling, induced deposition, etching,
and implantation, 5-10 nm minimum beam
diameter, ~30nm features milled. K. Edinger,
A. Stanishevsky, J. Orloff and J. Melngailis
- deep reactive ion beam etching, D. DeVoe
- aligner/bonder, R. Ghodssi
- new Engineering & Applied Sciences Bldg.
(6000 sq. ft. class 1000, clean room), ready May,04
Engineering and Applied Sciences Building
Clean room
floor plan
6000sq. ft.
Class 1000
Space
Cross section view of clean room and subfab
FIB
facilities
Micrion FIB-2500 system with 50 kV Ga+
source and 5nm minimum beam diameter
Nanofab 150 kV
FIB system with alloy
ion sources used for
implantation of
semiconductor devices
FEI-620 30 kV Dual-Beam SEM/FIB
with Ga+ ion source
FIB patterning of diamond films
Patterned CVD diamond
microcrystal
A. Stanishevsky, Univ. of
Trenches focused-ionbeam milled in a diamond
film.
30nm wide, 600nm deep
Focused Ion Beam Milled
Cross Section of Part of an Integrated Circuit
FIB/SEM fabricated NanoProbes
Klaus Edinger
Ion Beam Shaving
SNOM probe
Electrochemical
probe
Electron Beam Induced Deposition
Scanning Thermal
Probe
AFM / MFM
Probe
LIBRA
Focused Ion Beam Milling
Scanning Gas-Nozzle “Nano-jet”
Focused Ion Beam
Implantation
Scanning Electric Field Probe
Nanodevices-Electronic & optical
• quantum (C. H. Yang, et. al.)
• modeling: nanoMOSFET’s, carbon nanotubes
(N. Goldsman & G. Pennington)
• magnetic storage (R. Gomez, et al.)
• FIB implanted JFET (A. DeMarco & J. Melngailis)
• single photon tunneling (I. Smolyaninov & C. Davis)
Nanoelectronics Research
C.H. Yanga, M.J. Yangb, Andy Chenga, Philip Changa, and J.C. Culbertsonb
aDepartment of Electrical and Computer Engineering,University
bNaval Research Laboratory, Washington DC
of Maryland, College Park, Maryland
Fabricated 30 nm conducting
InAs wires by
L
(I) MBE growth of heterojunctions,
(II) electron beam lithography and
(III) wet etching
W
le
l
Observed:
1D pure metal regime:
W < le < l
Ballistic regime:
L < le < l
Nanoelectronics Research
C.H. Yanga, M.J. Yangb, Andy Chenga, Philip Changa, and J.C. Culbertsonb
aDepartment of Electrical and Computer Engineering,University
bNaval Research Laboratory, Washington DC
of Maryland, College Park, Maryland
Fabricated 100 nm diameter
conducting InAs ring, and
observed quantum interference
due to wave-like electron
transport.
Left: AFM topography
Below: Magnetoresistance
Numerical Boltzmann/Schrodinger Equations: CAD
..
of Quantum Effects in Nanoscale
Semiconductors
Neil Goldsman, ECE Dept. UMCP
Flow Chart
Band Diagram
Quantum Domain
Dispersion Relation of QM Well
Numerical Boltzmann/Schrodinger Equations: CAD
of Quantum Effects in Nanoscale
Semiconductors
..
Neil Goldsman, ECE Dept. UMCP Numerical
Subthreshold Characteristics
Current Vector(SHBTE)
I-V Charactistics
Current Vector(QM-SHBTE)
Design and Theory of Carbon Nanotube Diodes
by Gary Pennington and Neil Goldsman
ECE Department University of Maryland
•Results: Using the tube diameter dependence of the effective mass, band offset, dielectric
constant, and hole concentration for an array of Y-junction multiwalled carbon nanotubes, we
determined an theoretical analytical formula the junction current as a function of constituent tube
diameters.
Array of Y-junction carbon nanotubes
-V
Experiment:
C. Papadopoulos et al., Phys. Rev. Lett 85, 3476 (2000).
Demonstration of current-induced domain wall motion
for novel magnetic device applications
Mechanism:
s-d exchange interaction
L. Gan, S.H. Chung, K. Aschenbach, M.Dreyer and R.D. Gomez, IEEE Transactions on
Magnetics 36, 3047, 2000.
Ballistic
Nanocontact
Magnetic Random
Access
Memory
R.D. Gomez,
et al., Laboratory
for Physical
Sciences,
College Park MD
R.D.
Gomez,
Department
of Electrical
andMD
Computer Engineering
and
University
of Maryland,
College Park,
Demonstration of Fabrication and Characterization of
Single Domain Magnet Arrays
Topography of interacting NiFe island arrays
H. Koo and R.D. Gomez, IEEE Transactions on Magnetics 37.
Ballistic Nanocontact Magnetic Random Access Memory
R.D. Gomez, Department of Electrical and Computer Engineering
Single-Photon Tunneling
I.I. Smolyaninov, C.Davis
et.al. ECE Dept.
to PMT
fiber
3BCMU
gold film
pinhole
pr ism
632 nm
light
Schematic view of our experimental setup.
Small smart systems &MEMS
• Don Devoe- mechanical resonators…
• Reza Ghodssi- III-V MEMS, MEMS_VLSI integration
• Elisabeth Smela- polymer mEMS
High-Q Piezoelectric Nanomechanical Filter
Arrays
• Functional filter banks based on nano-scale
piezoelectric NEMS structures:
– orders-of-magnitude size reduction compared to SAW devices
– direct integration with VLSI (ZnO) and high-speed electronics
(AlAs)
– low power operation
• Applications
in miniature RF communications, spectrum
105
HTS
analyzers, etc.
104
Thin Crystal
piezo
NEMS.
Thin Film
103
Q
Dielectric
Planar
DielectricLumped
102
Element
10
1
10-10
10-8
10-6
10-4
Volume (cm3)
10-2
1
10+2
Piezoelectric resonator scaling
Input Signal
Top Pt
Bottom Pt
Output Signal
~~ 34
34m
m Deep
Deep
Trench in Si
PZT
SiO22
L=200nm
gap=L/10
L=30nm
gap=20nm
f=60MHz
f=3GHz
Mechanical & thermal devices
• Hugh Bruck - funcionally graded materials
• Klaus Edinger - scanning thermal nanoprobe
*>150. 0° C
Functionally Graded
Smart Thin Film
5 mm
145.0
140.0
Mf >Troom
Ms <Troom
ATC 1200
SPUTTERING MACHINE
135.0
130.0
Functionally
Graded Smart
Thin Film
125.0
*<123. 7° C
Out-of-plane
Displacement
“Microbubble”
1 mm
150.0
Infrared Temperature
Field
Microdevice Performance Characterization
“Micropump”
Fabrication of Functionally Graded Thin Films
Hugh Bruck
ME Dept
Force Modulation
Microscopy
Atomic Force
Microscopy
1 m
Nano Indenter XP
Dimension
3000 SPM
Nanoscale Material Property and Stress
Characterization
Film-substrate
interface
Before
Actuation
400 oC
T
After
Actuation
s = 100 MPa
t
Digital Image
Correlation
U-DISPLACEMENT
100 nm
100 nm
z
Finite Element
Analysis
Ms = 43 oC, Mf = 23 oC
V-DISPLACEMENT
150 nm
150 nm
Nanoscale Structure and Deformation
Characterization
T = 44 oC
r
Ms = 3 oC, Mf = -17 oC
Microscale Modeling of Device Performance
Scanning Thermal Probe
Klaus Edinger
LIBRA
Me3 MeCp Pt precursor deposits a
Pt/carbon mixture
Filament diameter ~ 30 nm
Tip end radius < 20 nm
Height: 2-5 m
Nanofabricated Scanning Thermal Probe
Klaus Edinger, LIBRA
LIBRA
•Passive mode: the resistance of the wire in contact with the sample is
measured, using a low current  temperature mapping
•Active mode: the wire is heated by applied an AC-current
 mapping of thermal conductivity and diffusivity.
• Free-standing 20-50 nm Pt “wire” grown by electron
beam induced deposition from an organometallic
precursor gas on an AFM type cantilever.
• Low thermal mass; high sensitivity; high spatial
resolution
Topographic image (left): Only the metal leads are
visible. The two buried resistors are indicated by the
dotted line. Temperature image (right): The two
buried resistors (heating current ~2mA) are visible.
Summary
• nanofabrication capabilities (e-beam/SEM, focused ion
beam, MEMS, new EAS Building with clean room)
• nanodevices: electrical & optical
• nanoMEMS
• mechanical and thermal devices