Transparent Conductors

Transparent Conductors (TCO) available with many different thicknesses and resistances.

ito

I.T.O. (Indium Tin Oxide)

Ratio 90-10 / 95-5 mole percentage
Neutral Yellow in color

Standard resistances: 1 ohm/sq – 500 ohm/sq

I.T.O continues to be king among all transparent conductors.  Most commonly used in all flat panel displays, LCD, Oled, LCO’s, touch screens, P-caps, heaters, EMI-shielding, circuits, MEMS and solar applications.

ViewSpecs

izo

I.Z.O. (Indium Zinc Oxide)

Ratio 91-9 mole percentage
Yellowish in color

Standard resistances: 10 ohm/sq – 300 ohm/sq

Since the beginning 2002, it’s usage as a substitute for I.T.O. (in the LCD Market) has diminished in current years. It is easily etchable, but not as environmentally durable as I.T.O.  I.Z.O. .Exhibits poor water stability with time and temperature, and is very sensitive to wet chemistry.

ViewSpecs

azo

A.Z.O. (Zinc Oxide with Aluminum)

2% mole percentage of Al in Zinc Oxide
Neutral – Yellow in color

Standard resistances: 30 ohm/sq – 2000 ohm/sq

Commonly used for capacitive touch screens and other high resistive applications, such as antistatic discharge. A.Z.O. is an old technology commonly used for CRT.

ViewSpecs

fto

F.T.O. (Fluorine doped Tin Oxide) CVD

Neutral color – Hazy in color

Standard resistances: 7 ohm/sq – 30 ohm/sq

F.T.O. is the most stable, durable, and robust, as well as the oldest transparent conductor.  It can only be produced by CVD process and can be difficult to etch fine patterns  ≤50 µm. F.T.O. was primarily used for plasma displays and low E architecture glass applications. It is now much more common to see it’s usage in solar panels such as CIGS.

TFD has been able to coat F.T.O. on glass as thin as 0.7&1.1 mm on a routine basis.

ViewSpecs

wrtco

W.R.T.C.O.™ (Wide Range TCO)

Custom mixed TCO from 400nm-2500nm
Neutral – Light Yellow in color

Standard resistances: 10 ohm/sq – 50 ohm/sq

TFD has developed this unique, low resistance but highly durable coating for wide range of wavelength from 400-2500nm..

ViewSpecs

TFD pioneered and invented Planar Ion Beam Sputtering (IBS) for large area coating process.  This technique is different than plain magnetron sputter process.  (For superior than Ion beam Assist e – beam)

This process provides very low surface roughness, i.e. I.T.O. (RMS ≤ 7 Angstroms @ 1450 Angstroms and higher work function (W.F.) ≥4.8 ev)

This is an excellent choice to manufacturing devices such as Oled, MEM’s & Organic Solar (OPV)           

The IBS process provides an excellent adhesion, abrasion, higher compact density ≥ 99% and extremely stoichiometric, where E-Beam and Ion assisted E-Beam cannot match the quality

TFD Produced TCO's vs Competition
Figures of Merit T.F.D., IBS Process E-beam with Ion gun
IBS
Ion-Beam Sputtering
Bulk Resistance
ohm/cm
Thickness Å Resistivity @ 250°c Resistivity @ 60°c T% after crystallization at 550 ASIS T% @ 550 nm @250 ±25 T% color Visual Figure of Merit Figure of Merit
I.T.O.
a.90:10
2.0 x 10-4 1450 ±100 15±3 25±3 88% 85% Clear/ Neutral 89.2 73
b.95:5 1.8 x 10-4 1450 ±100 12±3 20±3 88% 85% Clear/ Neutral 89.0 74
I.Z.O. 3.5 x 10-4 1450 ±100 20±5 40±5 85% 82% Very Yellowish 44.84 Not Available
A.Z.O. 3.5 x 10-3 1450 ±100 ≤100 ≤300 85% 83% Clear/ Neutral 4.48 Not Available
F.T.O. 4.0 x 10-4 1450 ±100 20±5 N/A 80% 80% Haze/ Scatter 36.0 Not Available
WRTCO/
VIS-NIR
3.7- x 10-4 1450 ±100 20±2 35±5 85% 84% Clear Lt- Yellow 73 Not Available
NOTE 1: Ion assist with E-beam I.T.O. coating is extremely poor in quality for devices – Very rough absorption, reproductively and control is extremely poor and non stoichiometric.
NOTE 2: Ion-assist E-beam on metalitic target produces highly absorptive films, and only is used for optical filter applications.
QCinspec4
QCinspec
Common Applications: Guide for Products

Design Application
Commonly Used
Resistance Ohm/Sq

T%

Etchability Patterning

Typical Coatings Used

Max Size
LCD
Type: TN
300-500 See Curves Below Yes I.T.O. 10.1"
Type: STN
300-500 See Curves Below Yes I.T.O. 21"
Type: TFT 10-50 See Curves Below Yes I.T.O./ I.Z.O./ A.G.Z.O. 100"
Touch Screen
Resistive P-Cap
300±50
120-20
See Curves Below Yes I.T.O./ Dielect 23"
Heaters
115V
28V
12V

20-200
10-20
4-10

See Curves Below

N/A

I.T.O./ I.M.I.T.O™

All Sizes
E.M.I. 4-10 See Curves Below N/A I.T.O./ I.M.I.T.O™ 72"
E.M.P. 4-1 See Curves Below N/A I.T.O./ I.M.I.T.O™ 72"
Sttic Discharge 5K-50K See Curves Below N/A N/A All Sizes
OLED
Small Molecule
Large Molecule

40-80
12±3

See Curves Below

Yes

I.T.O.

All Sizes
OPV
Thin Film Polymer

≤10-2

See Curves Below

Yes

I.T.O./ F.T.O.

All Sizes
glassinspect1

10K Lux inspection

QCGrn2
PattPnlEdge

Color filter for LCD

PattPnlLrg3 copy
PattPnlLrg2 copy
Guidelines to Develop Your Product
(with TFD Supplied TCO's)
I.T.O. I.Z.O. A.Z.O. F.T.O. W.R.T.C.O.™
(VIS-NIR)
Applications Displays/ LCD/OLED Displays Displays/Solar Solar/ Plasma Military Filters
Wave Lengths 400-700nm 400-700nm 400-1500nm 400-1500nm 400-2500nm
TFD Process Planar Ion Beam
Magnetron Sputtering (IBS)
IBS IBS CVD IBS
Resistivity
(commonly available)
1-500 Ω/ Sq 10-100 Ω/ Sq 30-2000 Ω/ Sq 7-30 Ω/ Sq 10-50 Ω/ Sq
Optical Index (n,k) (Visible Spectrum)
See Data Below
See Data Below See Data Below See Data Below See Data Below
Surface Roughness
@1450-2000Å
7Å (RMS) 7Å (RMS) 7Å (RMS) 3-50Å (RMS) 15Å (RMS)
Work Function ≥ 4.8 ev ≥ 4.7 ev 4.3- 4.5 ev 4.3- 4.5 ev ≥ 4.6 ev
Etchability/Quality
CD (Critical Dim)
≤ 5 μm
Features/excellent
≈10μm /good ≥10μm /good ≥50μm /good ≥10μm /good
Uniformity
14"x14" and 24"x24"
± 2.5% across
Dimensions Available 18" x 20" / 28" x 36"or smaller
Shapes Flat, Curved, Domed, Cupped, and Rod
Coated Substrates
Available
Glass, Float, Borofloat, Corning, Sapphire, Quartz, Silicon
Mil- Spec: Mil T% & Ref% 14860B
Adhesion/Abrasion Mil C14806B
Mil C-675B
Mil C-48497
Quality Syst: Mil-I-45208
ISO 9001-2001