1.31µm VCSEL (2/2) 932001INER013 1

1.2 4 5 6 7 8... 12...23 2

a MOCVD 2 %InGaAsN SQW photoluminescencepl. 11 b MBE 5.3 %InGaAsN SQW........ 11 InGaAlAs...... 12 a InP/InGaAlAsInAlAs/InGaAlAs 35 DBR...13 b InP/InGaAlAs InAlAs/InGaAlAs 35 DBR (I-V)....13 1550nm VCSEL...13 a VCSEL.14 b VCSEL PL..14 a VCSEL.14 b VCSEL PL.14 a 16 b lasing lasing 16 1550 nm VCSEL 3

17 a 1550nm InGaAlAs... 18 b 1550nmInGaAlAs... 18... 19 probe-station 21 a 30µm 1550nmVCSEL 22 b 30µm 1550nmVCSEL L-I-V 22 4

(>0.5%)N-InGaAs MOCVD 1550 nm VCSEL DBR InGaAsAs 1550 nm VCSEL DBR DBR VCSEL InGaAlAs InP/InGaAlAs DBR 10 TiO 2 /SiO 2 DBR F-P (Fabry-Perot) dip 1558 nm lasing 1562nm 1nm 30mW 2KA/cm 2 1550nm VCSEL Trim 550 KeV VCSEL - - 5

In this project, 1550 nm VCSEL (Vertical-Cavity Surface-Emitting Laser) was epitaxy by MOCVD system has been simulated and fabricated using wafer bonding and proton-implanted. The processes and measurement systems of the 1550 nm VCSEL were also been established. Because of the wafer quality of N-InGaAs will degrade when the N content >0.5%, the material of active region in 1550nm is replaced by InGaAlAs, which is lattice matching with InP substrate. By concerning of wafer quality, the wafer consists of bottom-dbr and active region and the wafer only consist of top-dbr were respectively grown. These two wafers were bonded together successfully by wafer bonding. The VCSEL wafer consists of InP/InGaAlAs bottom-dbr, InGaAlAs active region and 10 pairs of TiO 2 /SiO 2 top-dbr was successfully optical pumped by 990nm Ti: sapphire laser. The F-P dip of the VCSEL was about at 1558 nm, the lasing wavelength is 1562 nm and the threshold pumping power is 30mW which is about 2KA/cm 2 of threshold current density. To optimize the opto-electronics characteristics of proton-implanted 1550 nm VCSEL, the energy of implanted was about 550 Kev obtained by the Trim simulator. Additionally, the opto-electronic measurement system of long wavelength was established to measure the L-I-V characteristics, near-field pattern and spectrum of the VCSEL. 6

1.55 µm (Vertical Cavity Surface Emitting Laser, VCSEL) 1300nm LED 850nm 1300nm 1550nm 1300nm~1550nm 1300nm~1550nm 1300nm 1550nm 7

UCSB,Walter Schottky Inst., NTT Photonics Lab., Alcatel, Noval Crystal Sandial Lab. [1] [4] [5] [10] 850nm 980nm 850nm ( Edge Emitting Laser, EEL) 1300nm 1550nm 1300 1550nm GaAs/InGaAs/A1GaAs 1.55 µm 8

1.55µm VCSEL N-InGaAs 1.45µm InGaAsP AlInGaAs MOCVD PL X-raySEMTEM DBR DBR GaAs InP 1. PECVD E-gun TiO 2 /SiO 2 TiO 2 /SiO 2 a-si/sio 2 a-si/mgo 2. AlGaAs/GaAs DBR DBR 9

MOCVD spectro- meter n-k analyzer DBR DBR δ- DBR 3. InP InGaAsP AlInGaAs DBR Sb- AlGaAsSb InP InP InP 1. 10

2. 1550 nm VCSEL 1550 nm VCSEL (1) VCSEL Bond-Pad (2) 1550nm VCSEL DBR active layer > 10µm DBR crack DBR Fusion Bonded (3) 11

1550nm VCSEL DBR 6~7µm (4) 1550nm VCSEL - - L-I-V near-field pattern 12

1. N InGaAs N InGaAs N single quantum-wellsqw 210k 1450nm (0.855KeV) 210k sample (b)mbe 5.3 % InGaAsN SQW photoluminescencepl 190k 1500nm 190k > 0.5% [11] 1550nm InGaAlAs 2.5 6 (d) Sample D intensity(a.u) 2.0 1.5 1.0 0.5 0.0 210K 180K 100K 70K 50K 10K Intensity (a. u.) 5 4 3 2 30K 40K 50K 70K 90K 110K 130K 150K 170K 190K 0.80 0.85 0.90 0.95 1.00 photon energy(ev) 1350 1400 1450 1500 1550 1600 1650 Wavelength (nm) (a)mocvd 2 %InGaAsN SQW(b)MBE 5.3 %InGaAsN SQW photoluminescencepl 13

2. InGaAlAs InP InGaAlAs InGaAlAs InP PL 1520nm Intensity (a.u.) 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 1350 1400 1450 1500 1550 1600 1650 1700 Wavelength InGaAlAs 1520nm 3. DBR InP DBR InP/InGaAlAs ( n = 0.34 )InAlAs/InGaAlAs ( n = 0.3 )InP/InGaAsP ( n = 0.27 ) InP/InGaAlAs InAlAs/InGaAlAs DBR 35 (a) 99% InP/InGaAlAs DBR 寛 (FWHM) 110 nm InAlAs/InGaAlAs DBR FWHM 100 nm (b) DBR InP/InGaAlAs DBR DBR 寛 InP/InGaAlAs DBR 14

R signal /R Au (%) 120 100 80 60 40 20 InP/InGaAlAs DBRs (a) InAlAs/InGaAlAs DBRs 0 1300 1400 1500 1600 1700 1800 Wavelength (nm) Current(mA) InP/InGaAlAsInAlAs/InGaAlAs 35 DBR (a) (b) I-V 0.6 0.4 0.2 0.0-0.2-0.4-0.6 (b) InAlAs/InGaAlAs DBRs InP/InGaAlAs DBRs -150-100 -50 0 50 100 150 Voltage drop(mv) 4. InP 35 InP/InGaAlAs DBR 2 2λ InGaAlAs 1/2λ InP spacer 10 TiO 2 /SiO 2 DBR DBR InGaAlAs 1/2 λ InP InGaAlAs (SC-MQWs) 1/2 λ InP InP 5/4 λ InGaAlAs 5/4 λ TiO 2 x10 SiO 2 2 λ cavity InP 1/4 λ InGaAlAs 1/4 λ InP substrate x35 15

R signal /R Au PL a TiO 2 /SiO 2 DBR VCSEL F-P dip 1558nm b VCSEL PL PL peak 1510nm 54nm (a)(b) DBR PL TiO 2 /SiO 2 DBR a F-P dip 1558nm PL b peak 1558nm 寛 3.3nm b b Q PL 54nm 3.3nm Q 470nm 100 50 0 0 1200 1400 1600 1800 1200 1400 1600 1800 Wavelength(nm) Wavelength(nm) a VCSEL b VCSEL PL R signal /R Au 100 50 0 1200 1400 1600 1800 Wavelength(nm) 16 PL intensity (a.u.) PL intensity (a.u.) 100 50 100 50 0 1200 1400 1600 1800 Wavelength(nm) a VCSEL b VCSEL PL

Ti:sapphire laser 990nm InGaAs Detector VCSEL optical pumping a b b VCSEL lasing 30mW 2KA/cm 2 1562nm 1nm InP/InGaAlAs DBR InGaAlAs VCSEL lasing Spectrometer Ti:sapphire laser λ p = p 990nm isolator F = 150mm F = 150mm @ room temperature sample a 4 1562 nm Measured output power (a.u.) 3 2 1 1 nm 1500 1550 1600 Wavelength(nm) 0 0 20 40 60 80 100 Pumping power (mw) 17 λ=1562 nm P th =30 mw Equivalent threshold current density = 2 KA/cm 2 b lasing lasing

1. DBR 6 µm 550KeV 480 KeV 480keV Concentration ( A. U.) 2.5 2.0 1.5 1.0 Energy 450 ev 500 ev 550 ev 0.5 0.0 0 1 2 3 4 5 6 Depth (µm) 18 P-DBR 1550 nm VCSEL

2. (1) VCSEL (life-time) a b (a) 1550nm InGaAlAs P-Type Top DBR InGaAlAs MQW active region Bottom DBR n-inp substrate b1550nmingaalas 19

bond-pad 100x100150x150200 x200 300x300µm2 102030µm (2) wafer bonding 35 DBR InGaAlAs 34 DBR DBR InP GaAs/AlAs DBR DBR 25 99% 35 InP/InGaAlAs DBR InGaAlAs 25 GaAs/AlAs DBR 600 o C VCSEL GaAs sub. GaAs sub. VCSEL structure MQW InP sub. InP sub. InP sub. InP sub. (3) 20

1550 nm VCSEL (a) (ACE)3 (b) (CH3OH)3 (c) (D. I. Water)3 (d) wafer bonding (e) (f) wafer bonding (g) AZ5214E (pattern) (h) Ti/Au (200Å/2000Å) (i) p-metal (j) Au/Ge/Ni/Au (200Å/400Å/140Å/ 2000Å) n-gaas subutrate (k) (RTA) 415 30 (anneal) (l) 1550nmVCSEL 21

DBR 6 µm AZ4620 (m) (n) (4) DBR p-alas/gaas n-inp/ingaalas DBR p-alas/gaas Ti/Au n-inp Au/Ge/Ni/Au 3. 1550nm VCSEL - - (L-I-V) (near-field pattern) (Labview) optical fiber + probe station 22 probe-station

(probe-station) VCSEL a 1550nmVCSEL b L-I-V L-I-V lasing 6 0.35 (a) Voltage (volt) 4 (b) IV LI @40 o C 0.30 0.25 0.20 0.15 Power (uw) 2 0.10 0.05 0 0 20 40 60 80 100 120 140 160 Forward current (ma) Leakage current Turn-on 30µm 1550nmVCSEL a bl-i-v 0.00 lasing 1. wafer bonding bonding 2. 4µm p mesa etching 23

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