1

doc.: IEEE 802.15-<15-06-0152-00-003c>

Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

Submission Title: [Metal-Insulator Electronics for 60 GHz and Beyond]Date Submitted: [7 March, 2006]Source: [Moddel, Garret] Company [Phiar Corp.]Address [2555 55th St., Bldg. D #104, Boulder CO, 80301]Voice:[(303) 443-0373], FAX: [], E-Mail:[adam@phiar.com]

Re: []

Abstract: [Metal-insulator devices have been developed for 60 GHz and beyond. The devices can be integrated into a CMOS process, and provide a low-cost, integratable technology for wireless applications]

Purpose: [Making the TG3c group aware of a non-semiconductor approach to mm-wave PHYs.]

Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

2

doc.: IEEE 802.15-<15-06-0152-00-003c>

Metal-Insulator Electronics:Metal-Insulator Electronics:Low Cost, CMOS-Compatible Devices Low Cost, CMOS-Compatible Devices

for 60 GHz and Beyond for 60 GHz and Beyond

IEEE 802.15.TG3c 6th Meeting – March 7, 2006

Garret ModdelChairman & CTO, Phiar Corp.Professor, University of Colorado

3

doc.: IEEE 802.15-<15-06-0152-00-003c>

Metal-Insulator Diode Detector

load

MIM diode

antenna

incident radiation

top metal

base metal

insulator

Top View

a “crystal radio” for ultra-high frequency electromagnetic waves

Side View

4

doc.: IEEE 802.15-<15-06-0152-00-003c>

Outline

• Metal-insulator technology– Diodes– Double-insulator diode– Detectors & modulators– Transistors

• Applications

5

doc.: IEEE 802.15-<15-06-0152-00-003c>

Metal-Insulator-Metal Diode Rectification

9.8

10.3

10.8

11.3

11.8

12.3

12.8

-20 0 20 40Distance ( Å )

Energ

y (

eV

)

Bias Voltage

Metal 1

Metal 2

Electron Tunneling

Insulator

• Carrier signal alternates polarity across diode

• Electrons tunnel preferentially in one direction due to difference in metal barrier heights

• Tunneling is extremely fast (~1 femtosecond) – allows for ultra-high carrier frequencies (> 1 terahertz)

6

doc.: IEEE 802.15-<15-06-0152-00-003c>

Current-Voltage Curves

Nonlinearity(curvature)

Slope determines resistance

Cur

rent

Voltage

Matching antenna

• Diode resistance should match antenna resistance - which is usually low

Sensitivity

• Detector responsivity (sensitivity) increases with nonlinearity

Double-insulator diode

• Large slope - matches antenna

• Large nonlinearity - high responsivity

Large nonlinearity

Large slope (low resistance)

Cur

rent

Voltage

MIM diode

MI-IM diode

7

doc.: IEEE 802.15-<15-06-0152-00-003c>

Double-Insulator Tunneling Diode

cathode anode

M1 M2I1 I2

Zero bias:

e-

cathode anode

Forward bias:

cathode anode

e-

Reverse bias:

Electron Transmission

Ene

rgy

(eV

)

910

11

12

13

14

15

10010-30

Quantumwells

• When Fermi level reaches quantum

well, electrons get a “free ride”

• Result: sharp turn-on

8

doc.: IEEE 802.15-<15-06-0152-00-003c>

Measured Diode I(V) Curves

• Reproducible

• Steep slope

• Sharp “knee”

• Low OFF current

Image Credit: Phiar. Contact pad design: Motorola.

9

doc.: IEEE 802.15-<15-06-0152-00-003c>

• Diode + antenna

Detectors & Modulators

Metal 1

Metal 2

Insulator 2

Insulator 1

Top Contact

BottomContact

ProtectiveInsulator

10

doc.: IEEE 802.15-<15-06-0152-00-003c>

200 GHz Testing

200 GHz Mixing Response*

• Removes effects from other physical mechanisms

• Results assure device truly operating at 200 GHz

* Testing performed at Harvard Smithsonian

-145

-135

-125

-115

-105

-95

-85

-75

-0.25 -0.15 -0.05 0.05 0.15 0.25

bias (V)

dB

m

measureddelta-f outputtheoreticaldelta-f output

11

doc.: IEEE 802.15-<15-06-0152-00-003c>

1 THz Testing

Signal Time SeriesDevice 1007-1-32

-1.0E-02

0.0E+00

1.0E-02

2.0E-02

3.0E-02

4.0E-02

5.0E-02

6.0E-02

-2.E-07 -1.E-07 0.E+00 1.E-07 2.E-07 3.E-07 4.E-07 5.E-07

Time (s)

Sig

nal

Vo

ltag

e (V

)

THz detector1 THz Pulsed Laser Response*

* Testing performed at UCSB

12

doc.: IEEE 802.15-<15-06-0152-00-003c>

Diode: Why It’s So Fast

• Short carrier transit time – because quantum mechanical tunneling

• Low lead parasitic resistance – because all metal & no semiconductor bulk to add high resistance

• Low RC time constanto Low capacitance (C) due to small diode areao Low resistance (R) due to

Double insulator large nonlinearityChoice of materials to produce low barrier

• Note: low resistance also improves impedance match of diode to antenna – improves efficiency

13

doc.: IEEE 802.15-<15-06-0152-00-003c>Antenna Innovation: Edge-Fed Antenna for Ultra-high Frequencies

200 GHz 20 GHz

• Separates carrier and signal frequencies

• Improves antenna efficiency

• Improves matching to diode

• Color code for this simulation: Blue = low poweryellow/green = high power

200 GHz carrier is received by antenna and channeled to diode region, where it is rectified

20 GHz rectified signal is channeled out the leads

14

doc.: IEEE 802.15-<15-06-0152-00-003c>

Traveling Wave Detector

overlap

MIIM waveguide

Vbias

antenna

top metal

bottom metal

tunneljunction plasmon wave

zy

x

Improves:• Efficiency• Impedance matching to antenna• RC time constant

Ex

Ey

Ez

15

doc.: IEEE 802.15-<15-06-0152-00-003c>

Comparison: THz Detectors

• Fast useful for heterodyne & direct detection• Sensitive high responsivity & low noise • Integratable thin film deposited at low temp on virtually

any substrate (plastic, glass, CMOS, GaAs, etc.)

Zero-Bias MIIM Diode

(simulated)

GaAs Schottky Diode

III-Sb Backward Tunnel Diode

Microbolometer

Bias Zero Positive Zero Positive

Responsivity

8-10 A/W 8 A/W 1-2 A/W 1-10 A/W

NEP ~110-12

W/Hz1/2 110-11 W/Hz1/2 N/A>110-12

W/Hz1/2

Bandwidth ~10 THz 25 THz 720 GHz < 1 MHz

16

doc.: IEEE 802.15-<15-06-0152-00-003c>Antenna Transmission & Reflection: Towards Modulation

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 1000 2000 3000 4000

Diode Resistance ( ohms )

Reflect

ed

& A

bso

rbed

Pow

er

Zdiode = Zo

reflected power

2

oLOAD

oLOAD

ZZZZ

R

0

0

0

0

0

-1.0 -0.5 0.0 0.5 1.0

Bias Voltage ( V )

Old MIM Technology

(divided by 10 6 )

New MIIM Technology

2

-1

3

1

Dark

Cu

rren

t (

mA

/cm

2 )

absorbed power

17

doc.: IEEE 802.15-<15-06-0152-00-003c>

Modulator Demonstration

0.0E+00

5.0E-06

1.0E-05

1.5E-05

2.0E-05

2.5E-05

3.0E-05

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Modulation Voltage (V)

Mo

du

lati

on

Sig

nal

(V

)

Signal

Noise

Phiar Modulator10 kHz modulation

18

doc.: IEEE 802.15-<15-06-0152-00-003c>

Metal-Insulator Tunneling Transistor

E

C

Bdouble-I emitter oxides

base metal

collector oxide

low substrate

narrow emitter stripe

19

doc.: IEEE 802.15-<15-06-0152-00-003c>

MIIMIM Tunneling Hot Electron Transistor

hot electron

emitter base collector

Cutoff freq, fT 1.8 THz

Max osc freq, fmax 3.8 THz

Unilateral pwr gain 20 dB

RF output pwr ~1 mW

Power efficiency > 30%

Predicted Performance

~ 10 nm

~ 10 nm

~ 6 nm

emitter metal

base metal

collector metal

collector insulator

emitter insulator (double-I)

20

doc.: IEEE 802.15-<15-06-0152-00-003c>

Energy Spread of Injected Electrons

Solution: MIIM emitter(chart at left)• Narrower hot electron

distribution• Lower energy hot electron

distribution

MIMIM

MIIMIM

J(E)

J(E)

0.0

0.2

0.4

0.0

0.2

En

erg

y (e

V)

0 4 8 12 16 20 Distance (nm)

hot electron current distribution

EF

EF

Problem: Energy spread reduces gain

• Low energy electrons clipped by barrier

• High energy electrons scatter

21

doc.: IEEE 802.15-<15-06-0152-00-003c>

275

300

400

3 THz

410

0 500 1000 1500 2000 2500 3000

GaN HEMTGaAs PHEMTGaAs MHEMT

InP HEMTInP HBT

SiGe HBTPhiar

Exceeding Other Transistor Technologies

Source: The International Technology Roadmap for Semiconductors: 2005; Phiar projections.

Maximum transistor frequencies: fmax (GHz)

Yellow: frequencies where engineering challenges remain

Technologies projected to hit “Brick Wall” by 2010 – further progress not expected.

150

250

22

doc.: IEEE 802.15-<15-06-0152-00-003c>Transistor: Why It’s So Fast

basecollector

emitter

low substrate

emitter oxides

base metal

collector oxide

Advantages over semiconductor transistors: • Transit time• Base & lead resistance• Integratable, etc.

Advantages over semiconductor transistors: • Transit time• Base & lead resistance• Integratable, etc.

23

doc.: IEEE 802.15-<15-06-0152-00-003c>The Basic Building Block: Metal-Insulator High-Frequency Transceiver

• Stand-alone device

or• Integrated onto chip

- - -• Wireline

or• Wireless

Thin film metal-insulatortransmitter and receiver

High speed semiconductor signal conditioning circuitry

Metal-insulator detectors have beendemonstrated on CMOS chips

24

doc.: IEEE 802.15-<15-06-0152-00-003c>Features of Metal-Insulator Technology

• Ultra-high-speed up to THz diodes & transistors• Thin film low-cost, large-area, integratable on

CMOS, plastic, etc.• No exotic materials or processes compatible with

CMOS fab• High efficiency practical• Low voltage compatible with CMOS• Low cost• One technology does it all: diodes, transistors,

antennas, arrays…

25

doc.: IEEE 802.15-<15-06-0152-00-003c>

Outline

• Metal-insulator technology– Diodes– Double-insulator diode– Detectors & modulators– Transistors

• Applications

26

doc.: IEEE 802.15-<15-06-0152-00-003c>Personal Area Networks: the 10 meter opportunity

27

doc.: IEEE 802.15-<15-06-0152-00-003c>Intra-box: the 10 cm opportunity

• Removes slow copper

• Provides design flexibility

GPU

CPU

28

doc.: IEEE 802.15-<15-06-0152-00-003c>

30 Years of Bandwidth

Source: IEEE Spectrum, “Edholm’s Law of Bandwidth: Telecommunications data rates are as predictable as Moore’s Law,” July 2004.

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

1976 1981 1986 1991 1996 2001 2006

Lo

g (

Bit

s p

er S

eco

nd

)

Wireless

10 Mb/s Etherne

t

9600 b/s Modem

1 Gb/s Etherne

t

802.11b

802.11g

GSM

MIMO

Wireline

“Nomadic”

29

doc.: IEEE 802.15-<15-06-0152-00-003c>

7.0

8.0

9.0

10.0

11.0

12.0

2005 2006 2007 2008 2009 2010

Lo

g (

Bit

s p

er

Se

co

nd

)Beyond Copper

Source: IEEE Spectrum, “Edholm’s Law of Bandwidth,” July 2004; Phiar estimates.

WirelineUWB at 0.48

& 1.2 Gb/s

“Pre-N” 802.11

Nomadic

Cellular

MIIM Technolog

y

MIIM Technolog

y

30

doc.: IEEE 802.15-<15-06-0152-00-003c>

RF-on-Flex Applications

• Low-cost radar (e.g., automotive)• Lightweight satellite uplinks/downlinks• Free-space data links, communications• RF ID tags and smart tags• Completely integrated phased arrays on flex• Very large aperture radar

Metal-insulator diodes have been demonstrated on plastic substrates

31

doc.: IEEE 802.15-<15-06-0152-00-003c>

Terahertz Radiation• T-rays (terahertz radiation) technology: One of “10

Emerging Technologies That Will Change Your World” (MIT Technology Review, Feb ‘04)

• Key to commercial success: low-cost T-ray source• Electromagnetic spectrum between high-frequency radio

waves and far infrared light • 0.1-10 THz range 0.03 - 3 mm wavelength• Non-ionizing, causes negligible damage of materials• Many materials transparent, others exhibit unique

absorption signature• Absorbed by water and humidity

– Absorption length 10 cm – 10 km in air, depending on wavelength and humidity

32

doc.: IEEE 802.15-<15-06-0152-00-003c>

ApplicationsNon-Destructive Testing THz Security Scanning

THz Medical ImagingmmW Automotive

Radar

33

doc.: IEEE 802.15-<15-06-0152-00-003c>

Conclusions

• Metal-insulator diodes & detectors have been demonstrated– To 200 GHz and beyond

– On CMOS integrated circuits

– On plastic substrates

• Double-insulator diodes provide enhanced performance• Metal-insulator modulators & transistors are feasible• Advantages include low cost, integratability, ultra-high

speed, compatible with CMOS fabrication• Near-term applications include 60 GHz wireless links• Longer-term applications include terahertz wireless links,

terahertz imaging, and ultra-high speed electronics

34

doc.: IEEE 802.15-<15-06-0152-00-003c>

Extra Slides

35

doc.: IEEE 802.15-<15-06-0152-00-003c>

Classical or Quantum Description?• Incident radiation

oElectromagnetic waves or oQED photons (quanta)

• Antenna signaloCurrent (classical) or oSurface plasmons (quanta)

• Diode tunnelingoRectification (classical) or oHot electrons (quanta) oroQuantum transitions

36

doc.: IEEE 802.15-<15-06-0152-00-003c>

Features of Transistor

• Ultra-fast metal-insulator nanotechnology transistors • Thin film: compatible with silicon ICs• Manufacturable at low cost

E

C

Bdouble-I emitter oxides

base metal

collector oxide

low substrate

narrow emitter stripe

38

doc.: IEEE 802.15-<15-06-0152-00-003c>

Double Insulator

0

0

0

0

0

-1.0 -0.5 0.0 0.5 1.0

Bias Voltage ( V )

Old MIM Technology

(divided by 106)

New MIIM Technology

2

-1

3

1

Dar

k C

urre

nt

(m

A/c

m2)

0

0

0

0

0

-1.0 -0.5 0.0 0.5 1.0

Bias Voltage ( V )

Old MIM Technology

(divided by 106)

New MIIM Technology

2

-1

3

1

Dar

k C

urre

nt

(m

A/c

m2)

39

doc.: IEEE 802.15-<15-06-0152-00-003c>

Comparison: THz Sources

• Efficient up to 35% or higher DC-to-THz• High power mW output for single device• Integrated solid state, thin film

SourceOperating

TemperatureCost

Phiar MIIMIM oscillator room $1 est.

Quantum Cascade Laser requires cooling

$1,000

est.

Microwave Upconverter low-room $100s – $1000sest.

Femtosecond Laser room $50,000+

Gas Laser room $300,000

40

doc.: IEEE 802.15-<15-06-0152-00-003c>

Emerging Market: Terahertz Imaging

• Security– Bombs in packages: mail packages, luggage – Objects detected through-wall and through-clothes– Chemical and biological materials

• Medical imaging– Oncology: imaging soft tissue for cancer– Dental images

• Pharmaceuticals– Drug dosage testing– Drug discovery

• Manufacturing non-destructive diagnostics– Packaged semiconductors– Plastic and foam materials

• Material composition analysis: food, textiles, asbestos• Gas analysis: pollution monitoring, engine exhaust, astronomy• Defense

– Imaging through obscurants (fog, smoke, etc.)– Chem/bio agent & target detection & identification– Free-space communications: high bandwidth & secure