École Polytechnique Fédérale de Lausanne · Web viewFigure 1: Reflection R and transmission T of...
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Projects at the EPFL Center of MicroNanoTechnology III-NITRIDE BASED BLUE VCSELS G. Cosendey, A. Castiglia, G. Rossbach, J.-F. Carlin, N. Grandjean (SB-IPHYS-LASPE) Laboratory of Advanced Semiconductors for Photonics and Electronics, EPFL Project objective: Highly-reflective dielectric-based distributed Bragg reflectors (DBRs) have been developed (Fig. 1) to serve as top mirror in blue vertical cavity surface emitting lasers (VCSELs). A schematic drawing and an SEM cross-section view of such a device are depicted in Fig. 2 and Fig. 3, respectively. Electroluminescence (EL) spectra measured below and above threshold on a blue VCSEL are shown in Fig. 4. 200 250 300 350 400 450 500 550 600 0 20 40 60 80 100 R T A = 1-(R +T) R , T , A (% ) W avelen g th (n m ) 137 nm R m ax = 99.7% S to p band w idth: Top dielectric D B R B ottom InAlN /G aN D BR M etalpads Figure 1: Reflection R and transmission T of a 7-pair SiO 2 /TiO 2 DBR. Figure 2: Schematic drawing of a monolithic nitride-based VCSEL. 1 mm 10 mm 400 410 420 430 440 E L in ten sity (arb .u n it) W avelen g th (n m ) 0.5 I th I th C avity (lasing)m ode B ragg m odes Figure 3: SEM cross-section view of a processed VCSEL. Figure 4: VCSEL EL spectra below and at lasing threshold. Techniques employed: E-beam evaporator (LAB600) for dielectric DBR deposition. Publications: [1] G. Cosendey, A. Castiglia, G. Rossbach, J.-F. Carlin, and N. Grandjean, Blue monolithic AlInN-based vertical cavity surface emitting laser diode 1
Transcript of École Polytechnique Fédérale de Lausanne · Web viewFigure 1: Reflection R and transmission T of...
Projects at the EPFL Center of MicroNanoTechnology
III-NITRIDE BASED BLUE VCSELS
G. Cosendey, A. Castiglia, G. Rossbach, J.-F. Carlin, N. Grandjean (SB-IPHYS-LASPE)Laboratory of Advanced Semiconductors for Photonics and Electronics, EPFL
Project objective:Highly-reflective dielectric-based distributed Bragg reflectors (DBRs) have been developed (Fig. 1) to serve as top mirror in blue vertical cavity surface emitting lasers (VCSELs). A schematic drawing and an SEM cross-section view of such a device are depicted in Fig. 2 and Fig. 3, respectively. Electroluminescence (EL) spectra measured below and above threshold on a blue VCSEL are shown in Fig. 4.
200 250 300 350 400 450 500 550 6000
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R T A = 1-(R+T)
R, T
, A (%
)
Wavelength (nm)
137 nm
Rmax = 99.7%
Stopband width:
Top dielectric DBR
Bottom InAlN/GaN DBR
Metal pads
Figure 1: Reflection R and transmission T of a 7-pair SiO2/TiO2 DBR.
Figure 2: Schematic drawing of a monolithic nitride-based VCSEL.
1 mm10 mm 400 410 420 430 440
EL in
tens
ity (a
rb. u
nit)
Wavelength (nm)
0.5 Ith Ith
Cavity (lasing) mode
Bragg modes
Figure 3: SEM cross-section view of a processed VCSEL.
Figure 4: VCSEL EL spectra below and at lasing threshold.
Techniques employed: E-beam evaporator (LAB600) for dielectric DBR deposition.Publications:[1] G. Cosendey, A. Castiglia, G. Rossbach, J.-F. Carlin, and N. Grandjean, Blue monolithic
AlInN-based vertical cavity surface emitting laser diode on free-standing GaN substrate, Appl. Phys. Lett. 101, 151113 (2012).
[2] G. Cosendey, J.-F. Carlin, N. A. K. Kaufmann, R. Butté, and N. Grandjean, Strain compensation in AlInN/GaN multilayers on GaN substrates: Application to the realization of defect-free Bragg reflectors, Appl. Phys. Lett. 98, 181111 (2011).
Funding: NCCR QP, FNS, CTI/KTI.
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