Conservation of quantum efficiency in quantum well intermixing by stress engineering with dielectric bilayers

In semiconductor lasers, quantum well intermixing (QWI) with high selectivity using dielectrics often results in lower quantum efficiency. In this paper, we report on an investigation regarding the effect of thermally induced dielectric stress on the quantum efficiency of quantum well structures in impurity-free vacancy disordering (IFVD) process using photoluminescence and device characterization in conjunction with microscopy. SiO2 and Si x O2/SrF2 (versus SrF2) films were employed for the enhancement and suppression of QWI, respectively. Large intermixing selectivity of 75 nm (125 meV), consistent with the theoretical modeling results, with negligible effect on the suppression region characteristics, was obtained. Si x O2 layer compensates for the large thermal expansion coefficient mismatch of SrF2 with the semiconductor and mitigates the detrimental effects of SrF2 without sacrificing its QWI benefits. The bilayer dielectric approach dramatically improved the dielectric–semiconductor interface quality. Fabricated high power semiconductor lasers demonstrated high quantum efficiency in the lasing region using the bilayer dielectric film during the intermixing process. Our results reveal that stress engineering in IFVD is essential and the thermal stress can be controlled by engineering the dielectric strain opening new perspectives for QWI of photonic devices.

[1]  M. T. Furtado,et al.  Impurity-induced disorder in strained InGaAs/GaAs quantum wells by Zn diffusion and thermal annealing , 1992 .

[2]  Christophe Vieu,et al.  Evidence of stress dependence in SiO2/Si3N4 encapsulation-based layer disordering of GaAs/AlGaAs quantum well heterostructures , 1997 .

[3]  O. Hulko,et al.  Quantitative compositional profiles of enhanced intermixing in GaAs/AlGaAs quantum well heterostructures annealed with and without a SiO2 cap layer , 2009 .

[4]  G. White,et al.  Thermal expansion of fluorites at high temperatures , 1986 .

[5]  Thomas Elsaesser,et al.  Catastrophic optical damage at front and rear facets of diode lasers , 2010 .

[6]  A. Pietrzak,et al.  Theoretical and experimental investigations of the limits to the maximum output power of laser diodes , 2010 .

[7]  Tien Khee Ng,et al.  Large bandgap blueshifts in the InGaP/InAlGaP laser structure using novel strain-induced quantum well intermixing , 2016 .

[8]  John H. Marsh,et al.  Selective quantum-well intermixing in GaAs-AlGaAs structures using impurity-free vacancy diffusion , 1997 .

[9]  R. Wolffenbuttel,et al.  Thermal annealing of thin PECVD silicon-oxide films for airgap-based optical filters , 2016 .

[10]  P. Bhattacharya,et al.  Determination of critical layer thickness and strain tensor in InxGa1−xAs/GaAs quantum‐well structures by x‐ray diffraction , 1993 .

[11]  Hideyuki Naito,et al.  Long-Term Reliability of 915-nm Broad-Area Laser Diodes Under 20-W CW Operation , 2015, IEEE Photonics Technology Letters.

[12]  Y. Ohki,et al.  25-W 915-nm Lasers With Window Structure Fabricated by Impurity-Free Vacancy Disordering (IFVD) , 2007, IEEE Journal of Selected Topics in Quantum Electronics.

[13]  Bocang Qiu,et al.  10-GHz Mode-Locked Extended Cavity Laser Integrated With Surface-Etched DBR Fabricated by Quantum-Well Intermixing , 2011, IEEE Photonics Technology Letters.

[14]  Nicholas J. Ekins-Daukes,et al.  Strain-Balanced Criteria for Multiple Quantum Well Structures and Its Signature in X-ray Rocking Curves† , 2002 .

[15]  H. Miyajima,et al.  High-Efficient and Reliable Broad-Area Laser Diodes With a Window Structure , 2013, IEEE Journal of Selected Topics in Quantum Electronics.

[16]  Abdullah Demir,et al.  29.5W continuous wave output from 100um wide laser diode , 2015, Photonics West - Lasers and Applications in Science and Engineering.

[17]  Atilla Aydinli,et al.  Impurity-free quantum well intermixing for large optical cavity high-power laser diode structures , 2016 .

[18]  Thomas F. Krauss,et al.  Postgrowth control of GaAs/AlGaAs quantum well shapes by impurity-free vacancy diffusion , 1994 .

[19]  Jae Su Yu,et al.  Fabrication of multi-wavelength In0.2Ga0.8As/GaAs multiple quantum well laser diodes by area-selective impurity-free vacancy disordering using SiOx capping layers with different stoichiometries , 2005 .

[20]  Jin Dong Song,et al.  Influence of dielectric deposition parameters on the In0.2Ga0.8As/GaAs quantum well intermixing by impurity-free vacancy disordering , 2002 .

[21]  Hiroshi Nishihara,et al.  Monolithic integration of laser and passive elements using selective QW disordering by RTA with SiO/sub 2/ caps of different thicknesses , 2001 .

[22]  L. Coldren,et al.  Diode Lasers and Photonic Integrated Circuits: Coldren/Diode Lasers 2E , 2012 .

[23]  Stephen J. Pearton,et al.  Kinetics of implantation enhanced interdiffusion of Ga and Al at GaAs‐GaxAl1−xAs interfaces , 1986 .

[24]  C. Jagadish,et al.  Effect of Stress on Impurity-Free Quantum Well Intermixing , 2001 .

[25]  John H. Marsh,et al.  Suppression of bandgap shifts in GaAs/AlGaAs quantum wells using strontium fluoride caps , 1992 .

[26]  J. M. Worlock,et al.  Strain-induced lateral confinement of excitons in GaAs-AlGaAs quantum well microstructures , 1988 .

[27]  Daniel Hofstetter,et al.  Quantum-well intermixing for fabrication of lasers and photonic integrated circuits , 1998 .

[28]  Wei Zhao,et al.  Thermal Stress in High Power Semiconductor Lasers , 2015 .

[29]  Peter W. Epperlein,et al.  Semiconductor Laser Engineering, Reliability and Diagnostics: A Practical Approach to High Power and Single Mode Devices , 2013 .

[30]  Erik Zucker,et al.  Semiconductor Laser Power Enhancement by Control of Gain and Power Profiles , 2015, IEEE Photonics Technology Letters.

[31]  Chennupati Jagadish,et al.  Influence of SiO2 and TiO2 dielectric layers on the atomic intermixing of InxGa1−xAs/InP quantum well structures , 2007 .

[32]  John H. Marsh,et al.  CW and mode-locked integrated extended cavity lasers fabricated using impurity free vacancy disordering , 1997 .

[33]  V. M. Glazov,et al.  Thermal expansion and heat capacity of GaAs and InAs , 2000 .

[34]  Daniel Hofstetter,et al.  Multiple wavelength Fabry–Pérot lasers fabricated by vacancy‐enhanced quantum well disordering , 1995 .

[35]  Chennupati Jagadish,et al.  Investigations of impurity-free vacancy disordering in (Al)InGaAs(P)/InGaAs quantum wells , 2010 .

[36]  Thomas Elsaesser,et al.  Physical limits of semiconductor laser operation: A time-resolved analysis of catastrophic optical damage , 2010 .