Tianjin University of Technology and Springer-Verlag Berlin Heidelberg 2011 C The GaAs based InGaAs metamorphic structures and their growth by molecular beam epitaxy (MBE) are investigated. The controlling of the source temperature is improved to realize the linearly graded InGaAs metamorphic structure precisely.The threading dislocations are reduced. We also optimize the growth and annealing parameters of the InGaAs quantum well (QW). The 1.3-m GaAs based metamorphic InGaAs QW is completed. A 1.3-m GaAs based metamorphic laser is reported.Among all kinds of photoelectric materials, the GaAs based 0.8 1.2 m near infrared material has been used widely. The GaAs based heteroepitaxial structures mainly include GaAlInAs materials. Considerable efforts have been devoted to GaAs based 1.3-m and beyond materials for their excellent performance such as low cost [1] , stable temperature characteristics [2] , compatible with the distributed Bragg reflectors [3] , and so on. Several structures, such as InGaAs quantum dot (QD), GaInNAs quantum well (QW), have been put forward. They have received great success in material growth and device fabrication around 1.3 m, but many problems will exist when the wavelength is extended to 1.55 m. On the research of GaInNAs(Sb) materials, 1.33-m and 1.59-m GaInNAs QW lasers emitting at room temperature (RT) have been realized [4][5][6][7][8] , but this kind of material is not stable enough for commercial production.In recent years, a metamorphic structure used in high electron mobility transistor (HEMT) materials has been paid much attention and introduced into GaAs based long wavelength light-emitting materials. Z. Mi et al [9] achieved 1.52-m RT emitting laser using InAs QD grown on InGaAs metamorphic buffer layer on GaAs substrate in 2008. However, no GaAs based QD laser emitting at 1.55 m has been realized.On the research of metamorphic InGaAs QW, I. Tangring [10] reported a 1.27-m metamorphic QW laser emitting at RT in 2006. Our group [11] cooperating with Chalmers University of Science and Technology researched the growth of metamorphic epitaxy materials, realized the high-quality 1.3-m continuous-wave (CW) semiconductor QW laser emitting at RT, extended the emission wavelength to 1.55 m and beyond, and reported a 1.58-m impulse-wave InGaAs metamorphic QW laser emitting at RT. All results above prove that the metamorphic structure is an efficient way to extend the emitting wavelength of GaAs based materials. In this paper, we investigate the growth of InGaAs/GaAs metamorphic materials by molecular beam epitaxy (MBE) and a CW 1.3-m low threshold current density InGaAs metamorphic QW laser emitting at RT, and further decrease the threshold current density from 490 A/cm 2 to 205 A/cm 2 compared with our previous work.All samples used in this study are grown on n + -GaAs (100) substrate by a solid source Veeco Mod Gen II MBE system. After removing the oxide, a 300-nm GaAs buffer is grown followed by the InGaAs linear metamorphic structure in which the In component increases linearly fr...