Solid State Lighting Michael Shur
Rensselaer Polytechnic Institute ECSE, Physics and Broadband Center http://nina.ecse.rpi.edu/shur
From a Torch to Blue and White LEDs and to Solid State Lamps Blue LED on Si, Courtesy of SET, Inc. http://nina.ecse.rpi.edu/shur/
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Research Areas • Plasma wave electronics
– THz resonant emission and detection
• Wide band gap materials and devices
– MOSHFET, UV LEDs, SAW, polarization, transport
• Sensitive skin
– Flexible substrates, nano gauges, electrotextiles, TFTs, OTFTs
• Novel device CAD
– AIM-Spice, opto/thermo/micro CAD
• Lab-on-the-WEB
– http://nina.ecse.rpi.edu/shur/remote
• Broadband center
http://nina.ecse.rpi.edu/shur
• Solid state lighting
http://nina.ecse.rpi.edu/shur/
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Talk Outline • History of General and Electric Lighting • Advantages of Solid State Lighting • Introduction to Photometry and Colorimetry • Optimization of Solid State Lamps • Emerging applications • Vision http://nina.ecse.rpi.edu/shur/
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Lighting – prerequisite of human civilization • 500,000 years ago- first torch • 70,000 years ago – first lamp (wick) • 1,000 BC – the first candle • 1772 - gas lighting • 1784 Agrand lamp the first lamp relied on research (Lavoisier) • 1826 -Limelight - solidstate lighting device • 1876 – Yablochkov candle • 1879 – Edison bulb
Yablochkov candle (1876)
Agrand lamp
Limelight
Edison bulb (1879)
http://nina.ecse.rpi.edu/shur/
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History of Electric Lighting • 1876 Pavel Yablochkov. First electric lighting device • 1879 Thomas Alva Edison. Incandescent lamp • 1897 Nernst. Filament made of cerium oxide-based solid electrolyte. • 1900 Peter Cooper Hewitt. Mercury vapor lamp. 1903. A. Just and F. Hanaman. Tungsten filament • 1904 Moor. Discharge lamps with air • 1907 H. J. Round. First LED (SiC) • 1910 P. Claude. Discharge lamps with inert gases • 1938 GE and Westinghouse Electric Corporation Fluorescent lamps.
http://nina.ecse.rpi.edu/shur/
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First LED (1907)
http://nina.ecse.rpi.edu/shur/
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Lighting in James Joyce Room Shakespeare Hotel, Bernadinu 8/8 Vilnius, Lithuania (09/05/02)
Incandescent
First LED stamp
Fluorescent http://nina.ecse.rpi.edu/shur/
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Benefits of LED Lighting An improvement of luminous efficiency by 1% saves 2 billions dollars per year. 10
100
8
80
6
60
4
40
2 0 2000
20 2010
2020 Year
Cost Savings $USB/yr
LED Penetration(%)
120 “High Investment Model”
2030
“Low Investment Model”
Data from R. Haitz, F. Kish, J. Tsao, and J. Nelson Innovation in Semiconductor Illumination: Opportunities for National Impact (2000)
http://nina.ecse.rpi.edu/shur/
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Solid State Lighting 100 80 60
Efficiency (lm/W)
40 20 0 Incandescent
Halogen
Fluorescent
White LED (2000)
White LED (2010)
120 100 80
Lifetime (1000 h)
2002
60 40 20 0 Incandescent
Halogen
Fluorescent
White LED (2000)
White LED (2010)
http://nina.ecse.rpi.edu/shur/
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Challenges of Solid State Lighting • Reduce cost • Improve efficiency of light generation • Improve efficiency of light extraction • Improve quality of light http://nina.ecse.rpi.edu/shur/
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Cost of Light
Fluorescent tubes: dollar per lumen 0.01 White LED: dollar per lumen 0.25 (Lumileds) 0.66 (Nichia)
•Incandescent bulbs: Dollar per lumen 1/1100 Re LED: dollar per lumen0.1
http://nina.ecse.rpi.edu/shur/
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Evolution of lm/package and cost/lm for red LEDs
After Roland Haitz Agilent Technologies
http://nina.ecse.rpi.edu/shur/
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Challenges in light extraction
epoxy ne
ns
Conventional LED chip grown on an absorbing substrate.
θc active layer
absorbing substrate
(b) High-brightness LED chip design with thick transparent window layers Light escapes through 6 cones
From A. Žukauskas, M. S. Shur, R. Gaska, MRS Bull. 26, 764, 2001. http://nina.ecse.rpi.edu/shur/
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Progress in AlInGaP LEDs
After http://www.lumileds.com/technology/tutorial/slide2.htm http://nina.ecse.rpi.edu/shur/
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Light Extraction : TIP-LEDs from LumiLeDs
Lum en/w att
1000 high pre ssu re so diu m 1 kW
TIP-LED
fluo res cen t 1 W m ercury vapor 1 kW
100
ha lo ge n 30 W Standard A lG a In P /G a P
10
tu ng ste n 6 0 W re d f ilt e r e d tu ng ste n 6 0 W
Top contact
1
550
600
650
700
750
P e ak w av elen gth (n m )
After M.O. HOLCOMB et al. (2001), Compound Semiconductor 7, 59, 2001). http://nina.ecse.rpi.edu/shur/
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Photometry: Eye sensitivity Photopic vision (cones) @ High Illumination
0
Relative Sensitivity
10
V'(λ)
V(λ)
-1
10
Scotopic vision (rods) @ Low illumination
-2
10
-3
10
-4
10
-5
10
400
500
600
Wavelength (nm)
700
800
Cones are red, green, and blue http://nina.ecse.rpi.edu/shur/ 16
Radiometry and Photometry Watt W/nm
Photopic vision eye sensitivity
Φυ = 683 lm W × ∫ Φ e V (λ ) dλ Luminous flux
W/nm Wavelength (nm)
Iυ = dΦυ dω = 683 lm W × ∫ I e V (λ ) dλ Luminous intensity 1/60 of the luminous intensity per square centimeter of a blackbody radiating at the temperature of 2,046 degrees Kelvin
(Candela = lm/sr – SI unit) Luminous efficiency: power into actuation of vision (lm/W) http://nina.ecse.rpi.edu/shur/
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How much light do you need? Type of Activity
Illuminance (lx =lm/m2)
Orientation and simple visual tasks (public spaces)
30-100
Common visual tasks (commercial, industrial and residential applications) Special visual tasks, including those with very small or very low contrast critical elements
300-1000 3,000-10,000
http://nina.ecse.rpi.edu/shur/
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Colorimetry: Chromaticity Coordinates 1931 CIE color matching functions: purple, green, and blue
X = ∫ x (λ ) S (λ ) dλ Y = ∫ y (λ ) S (λ ) dλ
2.0
_
z
blue
1.5
_
x
green _ y purple
1.0
0.5
0.0 350 400 450 500 550 600 650 700 750
Wavelength (nm)
Z = ∫ z (λ ) S (λ ) dλ
X x= X +Y + Z Y y= X +Y + Z
x+y+z = 1 http://nina.ecse.rpi.edu/shur/
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Color Coordinates [Y] 1.0
520 [G]
530
0.8
540
510
560
0.6 500 580 A
0
Is it really that bad? Just remember: White is Black!
640 700
0
,0
Red
[R]
00
10
00
C
4 ,0
490
600 620
2, 00 0
D 65 E B
3 ,0 0
0.4
6,
y Chromaticity Coordinate
Planckian locus (black body radiation)
Green
00
0.2 480
[B]
[Z]
0.0 0.0
Blue 460 400
0.2
0.4
0.6
0.8
[X] 1.0
x Chromaticity Coordinate http://nina.ecse.rpi.edu/shur/
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Color Mixing •Red, green, blue appear as white •Red and blue appear as magenta •Green and blue give cyan 0.8 •Red and green give yellow
520 530 540
y Chrom aticity Coordinate
510
YG
G 560
0.6 500
Y
580
0.4
600
O
C(W )
620 640
490
700
0.2 B
480
P
0.0 0.0
460
400
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
x Chromaticity Coordinate http://nina.ecse.rpi.edu/shur/
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Color Rendering 1.0 0.8
Light bluish green
Light grayish red
General Color Rendering Index Ra (CRI)
0.6 0.4 0.2 0.0 1.0 0.8
Dark grayish yellow
Light blue
Strong yellow green
Light violet
integrates the reflectivity data for 8 specified samples Special color rendering
0.6
Reflectivity
0.4 0.2 0.0 1.0 0.8
indices,
0.6 0.4 0.2 0.0 1.0 0.8
Moderate yellowish green
Light reddish purple
0.6 0.4 0.2 0.0
400
500
600
700
400
500
Wavelength (nm)
600
700
refer to six additional test samples Ra varies up to 100 100 is the best. Ra might be negative http://nina.ecse.rpi.edu/shur/
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Generating White Light Phosphor-conversion white LED
Multichip white LED
Phosphor layer
InGaN chip
http://nina.ecse.rpi.edu/shur/
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How to Optimize Solid State lamp: maximize the objective function (K )
Fσ
(λ1 , … , λ n , I 1 , … , I n ) = σK + (1 − σ )R a
where σ is the weight that controls the trade-off between the efficacy, K, and color rendering index, Ra λ1, λ2, λ3,… and I1, I2, I3 are the peak wavelengths and relative powers of the primary LEDs, respectively For a dichromatic lamp (two primary LEDs), the optimal solutions can be obtained by simple searching within the wavelength space involving complementary pairs of blue and yellow-green LEDs. . http://nina.ecse.rpi.edu/shur/
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481/580 nm
20
489/591 nm 0 380/569 nm -20
450/571 nm
-40
2 primary LEDs 496/635 nm
-60 0
100
200
300
400
Luminous Efficacy (lm/W)
General Color Rendering Index
General Color Rendering Index
Optimization of Polychromatic Solid-State White Lamps 100 456/537/601 nm
464/543/613 nm
80 454/543/597 nm
60 40 20
3 Primary LEDs
0 300
350
400
Luminous Efficacy (lm/W)
http://nina.ecse.rpi.edu/shur/
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99.5 99 98
5
4
General CRI
95 90
2 LEDs 3 LEDs 4 LEDs 5 LEDs
3
80 70 60 50 40 30 20 10 5
2 320
340
360
380
400
420
Luminous Efficacy (lm/W)
440
Peak wavelength (nm)
General CRI, Luminous Efficacy, and LED Wavelengths of Optimized Polychromatic Lamps 660 640 620 600 580 560 540 520 500 480 460 440 420
2 LEDs 3 LEDs 4 LEDs 5 LEDs
2
5 10 20 30 405060 70 80 90 95 98 9999.5
General CRI
The 30-nm line widths (A. Žukauskas, R. Vaicekauskas, F. Ivanauskas, R. Gaska and M. S. Shur, Optimization of White Polychromatic Semiconductor Lamps, Appl. Phys. Lett. 80, 234 (2002)). Crosses mark points that are suggested for highest reasonable CRI for each number of primary sources. http://nina.ecse.rpi.edu/shur/
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General color rendering index and efficacy for optimized polychromatic solid-state lamps (color temperature TS = 4870 K)
Type of lamp
Ra
Dichromatic Trichromatic Quadrichromatic Quintichromatic
3 85 98 99
Efficacy (lm/W) 430 366 332 324
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Peak wavelengths of primary LEDs (nm) for optimized polychromatic solid-state lamps (color temperature TS = 4870 K) blue
cyan green
452 453 454 448
509 493
537 531
yellow-green 571 561 572
amber to red 604 619 623
2 3 4 5
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A.Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Model spectra of white emission from quadrichromatic lamp (CT = 4870 K) for different points on optimal boundary of the (K,Ra) phase distribution
Power (arb. units)
K=332 lm/W Ra=98.5
AlGaInN
AlGaInP
K=351 lm/W Ra=95
K=362 lm/W Ra=90
K=370 lm/W Ra=85
400
450
500
550
600
650
Wavelength (nm)
From R. Gaska, A. Žukauskas, M. S. Shur, and M. A. Khan, "Progress in III-nitride based white light sources", (Invited paper), Volume 4776, pp. 82-96 (2002) http://nina.ecse.rpi.edu/shur/
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Optimization depends on color temperature 99
General CRI
98
2856 K 95
90
4870 K
80 320
340
360
380
400
420
Luminous Efficacy (lm/W)
Optimal boundaries of the (K,Ra) phase distribution for quadrichromatic lamps at two color temperatures From R. Gaska, A. Žukauskas, M. S. Shur, and M. A. Khan, "Progress in III-nitride based white light sources", (Invited paper), Volume 4776, pp. 82-96 (2002) http://nina.ecse.rpi.edu/shur/
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Luxeontm LED Combination 80
603-520-452 603-520-472
General CRI (points)
603-502-452
60
603-502-472 629-520-472
40
From theory to practice
629-520-452
20 645-520-452
0
629-502-472 645-520-472
-20 629-502-452
645-502-452
645-502-472
-40 16
18
20
22
24
26
Efficiency (lm/W) From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Four LED Segment 80
) (p
78
77
0-5
-5
2 3-5
603/520/452
-4 02
3 60
7 -4 0 2
52
60
76
4 2-
629-603-520-452
645-603-520-452
79
52
75 19.8
20.0
20.2
20.4
20.6
20.8
21.0
Efficiency (lm/W) From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Why do we need quadrichromatic lamp? 603-520-452-nm trichromatic 645-603-520-452-nm quadrichromatic
80 60 40 20
R14 Moderate olive green
R13 Light yellowish pink
R12 Strong blue
R11 Strong green
R10 Strong yellow
R9 Strong red
R8 Light reddish purple
R7 Light violet
R6 Light blue
R5 Light bluish green
R4 Moderate yellowish green
-60
R3 Strong yellow green
-40
R2 Dark grayish yellow
-20
R1 Light grayish red
0
Ra General
Color rendering (points)
100
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A.Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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U of V/SET/RPI Versatile Solid State Lamp Control unit PC
USB interface module
Lighting fixture Photodiode sensor
ADC Current regulators
Microcontroller
LED array
Power supply
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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High-power LED based Versatile White Multichip Lamp
http://nina.ecse.rpi.edu/shur/
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VSSL User Interface
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Receptor sensitivity (arb. units) Spectral power density (arb. units)
Color Temperature Control in a Quadrichromatic Source of White Light 100
(a )
4.0
L -ty p e
10 1
3.5
0 .1
M -ty p e
0 .0 1 2856 K
(b )
4870 K
(c )
5800 K
(d )
6504 K
Power per 3000 lm (W)
S -ty p e
3.0
603 nm
2.5 2.0 1.5 1.0
645 nm
452 nm
0.5
(e )
0.0 400
520 nm
500
600
W a w e le n g th (n m )
700
3000
4000
5000
6000
Color temperature (K)
From A. Zukauskas, R. Vaicekauskas, G. Kurilcik, Z. Bliznikas, K. Breive, J. Krupic, A. Rupsys, A. Novickovas, P. Vitta, A. Navickas, V. Raskauskas, M. S. Shur, and R. Gaska, Quadrichromatic white solid-state lamp with digital feedback, SPIE 5187-24 http://nina.ecse.rpi.edu/shur/
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Applications of U of V/RPI/SET quadrichromatic Versatile Solid-State Lamp: Phototherapy of seasonal affective disorder at Psychiatric Clinic of Vilnius University
• Seasonal affective disorder (SAD) strikes some people in the northern latitudes • Bright white light is known to counteract SAD • The exact mechanism of treatment is not known
http://nina.ecse.rpi.edu/shur/
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Preliminary results for SAD Treatment A pilot investigation of color temperature selection was carried out on healthy subjects. Preliminary results showed that subjects with the emotional scale exhibiting anxiety required light with a higher color temperature. http://nina.ecse.rpi.edu/shur/
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SEMICONDUCTOR MATERIALS SYSTEMS FOR HIGH BRIGHTNESS LEDs 2000
AlN C ZnS GaN ZnO SiC(4H) SiC(6H) ZnSe CdS AlP CdO SiC(3C) GaP ZnTe AlAs InN CdSe AlSb CdTe GaAs InP Si GaSb Ge InAs InSb 0
800 600 500
400
300
200 1
UV
IR 1
2
3
4
5
6
7
Band Gap Energy (eV) http://nina.ecse.rpi.edu/shur/
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6.0
350
5.0
300
250 4.0 Al Ga N 0.3 0.7 3.0
0.0
0.2 0.4 0.6 0.8 Al mole fraction
200 1.0
Emission Wavelength (nm)
Band gap (eV)
III-Nitride AlxGa1-xN UV Emitters require high Al molar fraction (X) AlGaN heterostructures involve strain and polarization: Strain Energy Band Engineering •Quaternary •Strain relief via superlattice buffers •MEMOCVD •Non-polar substrates
•Homoepitaxy Thermal and current management http://nina.ecse.rpi.edu/shur/
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Strain Energy Band Engineering Use strain controlling superlattices
Use AlGaInN - quaternary
Band Offset (eV)
Thickness, 60 nm 3
50
2
40
1 0
30
AlGaN 0.2
0.4
0.6
1
0.8
InGaN
-1 -2
20 10 0
Lattice mismatch (A)
0
0.2
0.4
0.6
0.8
1
Al Mole Fraction 0.1
AlGaN
0 0.2
0.4
0.6
0.8
-0.1 -0.2
InGaN
Critical thickness as a function of Al mole fraction in AlxGa1-xN/GaN: superlattice (solid line), 1 SIS structure (dashed line). From A. D. Bykhovski, B. L. Gelmont, and M. S. Shur, J. Appl. Phys. 81 (9), 6332-6338 (1997)
-0.3 -0.4
Molar Fraction of Al and In http://nina.ecse.rpi.edu/shur/
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PL Intensity (arb. units)
5 nm Al0.5Ga0.5N
20 nm AlN
AlN epilayer
Bulk AlN substrate
substrate
SiC substrate
240
260
280
300
Luminescence intensity (arb. units)
AlN/AlGaN Room Temperature Photoluminescence PL from edge @ L = 400 µm PL from edge @ L = 440 µm spontaneous PL
320
Wavelength (nm)
PL signal from MQWs on bulk AlN is approximately 28 times stronger compared to the structure grown over SiC. From R. Gaska, C. Chen, J. Yang, E. Kuokstis, A. Khan, G. Tamulaitis, I. Yilmaz, M. S. Shur, J. C. Rojo, L. Schowalter, . Deep-ultraviolet emission of AlGaN/AlN quantum wells on bulk AlN, accepted at APL
240
260
280
300
Wavelength (nm)
Stimulated emission at 258 nm. From R. Gaska, C. Chen, J. Yang, E. Kuokstis, A. Khan, G. Tamulaitis, I. Yilmaz, M. S. Shur, J. C. Rojo, L. Schowalter, . Deep-ultraviolet emission of AlGaN/AlN quantum wells on bulk AlN, accepted at APL
http://nina.ecse.rpi.edu/shur/
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Pulsed Atomic Epitaxy: A representative growth unit cell of PALE. New Development – MEMO-CVD
Time, sec.
http://nina.ecse.rpi.edu/shur/
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Ultimate heteroepitaxy: blue LED on Si
Courtesy of SET, Inc. http://nina.ecse.rpi.edu/shur/
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USC/SET UV LED for solid state lighting and homeland security
40
Current, mA
340 nm LED 30 325 nm LED 20
280 nm LED
10 0
0
2
278 nm
Normalized intensity, a.u.
50
4
6
8
10
From: 9nm
240 260 280 300 320 340 360 380 400 420 440
EQE, %
0.2
0
200 400 600 800 1000
Current, mA
5
Output power, mW
Power, mW
340 nm 325 nm 280 nm
0.4
0.0
10
10.2nm
Wavelength, nm
0.6
15
8.5nm
RT 500 ns 10 kHz
Voltage, V 20
325 nm 338 nm
10
1
A. Chitnis, V. Adivarahan, J. Zhang, M. Shatalov, S. Wu, J. Yang, G. Simin, M. Asif Khan, X. Hu, Q. Fareed, R. Gaska, and M. S. Shur, Milliwatt power AlGaN quantum well deep ultraviolet Light emitting diodes, physics status solidi (2003) To be published
pulse 1A
dc 100 mA
0.1 0
0
200
400
600
Current, mA
800
1000
270 280 290 300 310 320 330 340 350
Wavelength, nm http://nina.ecse.rpi.edu/shur/
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Sub-milliwatt power 285 nm Emission UV LED on Sapphire. 30 14
Rs~70-80 Ω
20
10
15 10
p-AlGaN
5
SQW
0
RT dc
12
Power, µW
p+-GaN
Current, mA
25
8 6 4 2
0
2
4
n+-AlGaN buffer
6
0
8
0
40
60
80
100
400
500
Current, mA
Voltage, V
SL
0.20
LT-AlN
RT pulse 500 ns, 0.5%
285.5 nm 200 mA pulsed pumping 500 ns, 10 kHz
Power, mW
Intensity, a.u.
0.15
Sapphire
20
0.10
0.05
0.00 260
280
300
320
340
360 380
Wavelength, nm
400 420
0
100
200
300
Current, mA
V. Adivarahan, S. Wu, A. Chitnis, R. Pachipulusu, V. Mandavilli, M. Shatalov, J. P. Zhang, M. Asif Khan, G. Tamulaitis, A Sereika, I. Yilmaz, M. S. Shur, and R. Gaska, AlGaN Single Quantum Well Light Emitting Diodes with Emission at 285 nm, Appl. Phys. Lett., Vol. 81, Issue 19, pp. 3666-3668 (2002) http://nina.ecse.rpi.edu/shur/
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Solid State Lighting Funding
Nothing comes from nothing (Fresco at Vilnius University) http://nina.ecse.rpi.edu/shur/
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US DOE Mission Statement Develop viable methodologies to conserve 50% of electric lighting load by the year 2010 From Status Report: Edward D. Petrow DOE’s Solid State Lighting Initiative For General Illumination Photonics West January 24, 2001 San Jose, CA
San Francisco, California, June 24, 2002 U.S. Secretary of Energy Spencer Abraham told the United States Energy Association that his department is exploring the use of solid-state lighting utilizing Light Emitting Diodes (LEDs) as part of its ongoing campaign to reduce energy usage in the U.S. He displayed a Luxeon LED light source from Lumileds Lighting and called high-power LEDs "a revolutionary technological innovation that promises to change the way we light our homes and businesses."
White 5 W 120 lm 5500 K color temperature Lumileds Luxeon
http://nina.ecse.rpi.edu/shur/
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How energy saving will be achieved R&D Topic Area
% of Goal
New Light Sources
25%
Solid State Lighting
45%
Advanced Electronics & Integrated Controls
15%
Improved Fixtures & Market Penetration
10%
Human Factors
5%
From Status Report: Edward D. Petrow DOE’s Solid State Lighting Initiative For General Illumination, Photonics West January 24, 2001 San Jose, CA http://nina.ecse.rpi.edu/shur/
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DOE Energy Saving Projection 8 7 6
Quads, PEC
Baseline
5
Low SSL Penetration
4
High SSL Penetration
3 2 1
Initial Projection
0 2000
2004
2008
2012
2016
2020
Note: The projection assumes a constant primary energy consumption conversion ratio of 3.22 from end-use electricity to PEC. (source: BTS Core Databook, 2000)
From Status Report: Edward D. Petrow DOE’s Solid State Lighting Initiative For General Illumination,
Photonics West January 24, 2001 San Jose, CA
http://nina.ecse.rpi.edu/shur/
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LED Applications
http://nina.ecse.rpi.edu/shur/
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LED Applications Signals and Displays •POWER SIGNALS •Traffic Lights •Automotive Signage •Miscellaneous Signage •DISPLAYS •Alphanumeric Displays •Full Color Video Displays
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LED Applications (Biomedical) • MEDICAL APPLICATIONS
– Phototherapy of Neonatal Jaundice – Photodynamic Therapy – Photopolymerization of Dental Composites
– Phototherapy of Seasonal Affective Disorder • PHOTOSYNTHESIS – Plant Growing – Photobioreactors
• OPTICAL MEASUREMENTS
– Fluorescent Sensors – Time-Domain and Frequency-Domain Spectroscopy – Other Optical Applications http://nina.ecse.rpi.edu/shur/
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LED-Based Fluorimetry (b)
(a) LED
PD C LED
L
FF
EF
FF
EF
L
C
(c)
LED
C
EF
PD FF
FC L
PD
L
•Design versatility •Low-noise response •Electronic modulation •Low heat production •Small dimensions •Longevity •Durability •Low cost
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UV-LED Based Fluorimeter with Integrated Lock-in Amplifier
http://nina.ecse.rpi.edu/shur/
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LED Applications - Lighting • ILLUMINATION – Local Illumination – General Lighting
Parabolic Reflector
Cone Reflector Fresnel Lens LED array
LED Floodlight (after A.García-Botella et al., J. IES 29, 135, 2000) http://nina.ecse.rpi.edu/shur/
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General Lighting http://nina.ecse.rpi.edu/shur/
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Solid State Lighting - To probe further: Book A. Žukauskas, M. S. Shur, and R. Gaska, Introduction to Solid State Lighting, John Wiley and Sons, 2002, ISBN: 0471215740 Reviews/chapters: A. Žukauskas, R. Vaicekauskas, F. Ivanauskas, M. S. Shur and R. Gaska, Optimization of white all-semiconductor lamp for solid-state lighting applications, in in Frontiers in Electronics: Future Chips Proceedings of the 2002 Workshop on Frontiers in Electronics (Wofe-02) St. Croix, Virgin Islands, World Scientific Pub Co; (January 15, 2003), R. Gaska, A. Žukauskas, M. S. Shur, and M. A. Khan, Progress in III-nitride based white light sources, in SPIE Proceedings, to be published (Invited paper) A. Žukauskas, M. S. Shur, and R. Gaska, Solid State Lighting, in: Future Trends in Microelectronics: The Nano Millennium, New York: Wiley, 2002, S. Luryi, J. M. Xu, and A. Zaslavsky, eds. A. Žukauskas, M. S. Shur, and R. Gaska, Light-emitting diodes: progress in solid-state lighting, MRS Bulletin, pp. 764-769, October (2001) A. Žukauskas, M. S. Shur, R. Gaska, Solid-State Lamps, McGraw Hill Technical Encyclopedia
E-mail:
[email protected]
M. Asif Khan, J. Yang, G. Simin, R. Gaska, and M. S. Shur, Strain energy band engineering approach to AlN/GaN/InN heterojunction devices, pp. 195-214, in Frontiers in Electronics: Future Chips Proceedings of the 2002 Workshop on Frontiers in Electronics (Wofe-02) St. Croix, Virgin Islands, World Scientific Pub Co; (January 15, 2003), http://nina.ecse.rpi.edu/shur/
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Conclusion “... it is vital to know that the LED is an ultimate form of lamp, in principle and in practice, and that its development indeed can and will continue until all power levels and colors are realized.”
HOLONYAK, N., JR. (2000), “Is the light emitting diode (LED) an ultimate lamp?” Am. J. Phys. 68 (9), pp. 864-866.
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Appendix: Math of Color Rendering
Reference source
S r (λ )→ S r (λ ) ρi (λ ), i = 1, … ,8
Test source
S k (λ )→ S k (λ ) ρi (λ ), i = 1,…,8
USC chromaticity coordinates
u = 4 x (− 2 x + 12 y + 3) , v = 6 y (− 2 x + 12 y + 3)
General color rendering index (CRI)
1 Ra = 8
8
∑ Ri i =1
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where Ri is
{
′ − u r ) − Wri (u ri − u r )]2 + = 100 − 4.60 [Wki − Wri ]2 + 13 2 [Wki (u ki ′ − v r ) − Wri (v ri − v r )] 13 [Wki (v ki
}
2 12
2
.
W = 25Y 1 3 − 17 c = (4 − u − 10v ) v d = (1.708v + 0.404 − 1.481u ) v 10.872 + 0.404 c r c ki c k − 4 d r d ki d k ′ = u ki 16.518 + 1.481 c r c ki c k − d r d ki d k 5.520 ′ v ki = 16.518 + 1.481 c r c ki c k − d r d ki d k http://nina.ecse.rpi.edu/shur/
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Primary Energy Consumption in Buildings by End Use (US, 1998) Unallocated
2.6 Quads (7%) From Status Report: Other Edward D. Petrow 1.3 Quads (4%) DOE’s Solid State Lighting Appliances Initiative For General Illumination 5.0 Quads (14%) Photonics West January 24, 2001 San Jose, CA
Refrigeration
Lighting 6.0 Quads (17%)
36.3 Quads Space Heating
2.4 Quads (7%)
9.4 Quads (25%)
Water Heating 4.1 Quads (11%)
1 Quad = 1015 BTU (~8x 109 gallon of gas)
Ventilation
1.2 Quads (3%)
Space Cooling 4.3 Quads (12%) http://nina.ecse.rpi.edu/shur/
Source: BTS Core Databook, August 2000, Table 1.1.7 and Industrial Building Estimate from Table 1.3.11
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C L′
Cost of light • Estimated from C L′ 6 3 C1kWh C1Mlmh ≈ 10 + 10 the cost of the ′L ′L P τ η η L L lamp and the electric power consumed divided C L′ cost of the bulb by the amount of C1kWh price of 1 kW·h power luminous efficiency η ′L lumens produced wattage over the lifetime. PL τL lifetime of the lamp For 1 Mlm⋅h, this yields a cost http://nina.ecse.rpi.edu/shur/
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