The 16th Opto-Electronics And Communications Conference, OECC 2011 July 4-8,2011, Kaohsiung, Taiwan Stripe Width Dependence of Internal Quantum Effciency and Carrier Injection Delay in Lateral Current Injection GaInAsP/InP Lasers M. Futami*, T. Shindo*, T. Okumura*, R. Osabe*, D. Takahashi*, T. Koguchi*, T. Amemiya**, N. Nishiyama*, s. Arai** * Tokyo Institute of Technology, Dept. of Electrical and Electronic Engineering. ** Quantum Nanoelectronics Research Center. 7F-704. S-9. 2-12-1 O-okayama. Meguro-ku Tokyo 152-8552. Japan Tel :+81-3-5734-2555 Fax:+81-3-5734-2907 Email: ftami.m.aa@m.titech.ac.p, arai@pe.titech.ac.jp Abstract Interal quantum effciency and carrier injection delay time in lateral-current-injection (LCI) lasers fabricated on a semi-insulating (SI)-InP substrate were evaluated for various stipe widths. As the results, it was confred that narrower stipe width « 2 fl ) can give better static and dynamic performances. 1. Introduction Semiconductor lasers based on high index-contast waveguides have been getting much attention for compact and low power consumption photonic integrated circuits. As one of promising light sources, we proposed a GaInAsP/InP membrane distibuted feedback laser which consists of a thin semiconductor core layer sandwiched by polymer claddings [1], and demonstated low threshold operation under an optical pumping [2]. A lateral current injection (LCI) stucture [3] was adopted to realize injection type membrane laser, and its room-temperature continuous-wave (RT-CW) operation was achieved with a LCI buried-hetero stucture (BH) laser fabricated on a Si-InP substrate [4]. A injection type membrane DFB laser was recently reported [5], however poor lasing performances compared to those of conventional lasers with vertical injection stucture remain key issues. In order to realize better performances of the LCI membrane lasers, effcient carrier injection into the thin semiconductor core layer is essentially required. In this 468 1>-GalnAs contact Ws Fig. 1 Cross-sectional structure ofLCI lasers on SI-InP. L' :OO pm RT-CW % � � I � O � � � = 3 � l� ) =� � O � � 5 0 · Curent J m nm Fig.2 Lasing characteristics of LCI laser fr various stripe widths. paper, we discuss stipe width dependence of the interal quantum efciency measured fom static lasing characteristics as well as the carrier injection delay time measured fom direct modulation characteristics of LCI lasers fabricated on a Si-InP substate. 2. Experiment LCI lasers were fabricated by two-step OMVPE regrowth on a Si-InP substrate [4]. Figure 1 shows a cross-sectional stucture of the fabricated LCI laser. As can be seen, a GalAsP core layer (400 n thick), consisting of compressively-strained 5 quantum-wells