## 1 Introduction  
In the research fields of quantum information and quantum communications, single photons have attracted significant attention as they are fundamental elements for current quantum technologies [1; 2; 3]. Currently, quantum technologies are undergoing a revolution as the research on integrated quantum photonic circuits (QPCs) opens up exciting opportunities to implement complex quantum algorithms on single chips. For realization of QPCs, single photon sources and processing devices as well as photon detectors have to be combined together on single chips. The single photon sources need to be integrated into quantum photonic circuits to realize on-chip systems by directly coupling with nano-photonic devices via low loss waveguides. Therefore, an efficient coupling of single photon sources with waveguides remains an attracting issue, as the waveguide coupled single photon source is the key component of a QPC. Many efforts to place single photon sources in or on waveguides have been reported based on single photons generated from the NV-center in nano-diamonds [4], quantum dots (QDs) [5; 6], and single walled carbon nanotubes [7]. Compared with other kinds of single photon emitters, self-assembled quantum dots are very attractive candidates as they meet the requirements of high extraction efficiency,narrow emission linewidth, high single photon emission purity, stability, and so on. Integration of QDs with circuit elements has also been demonstrated by structuring the semiconductor material [8]. Among them, semiconductor III-V QDs are an ideal choice for implementing hybrid integrated QPCs for their high performance of emitting near-ideal single photons with ultrahigh brightness and indistinguishability, which also can be site-controlled and compatible with semiconductor manufacturing technology [9; 10; 11]. Embedding of III-V QDs into integrated quantum circuits has been realized by various approaches [12; 13; 14]. In these works, special methods or techniques are used to integrate III-V QDs on photonic chip such as wafer bonding, the micromanipulation method, or by the \"pick-place\" technique [12; 14; 15], which makes the implementation not as easy. Moreover, as the development of highly-integrated systems that can solve complex problems mostly depends on the system efficiency, photon flux, passive losses, and detection efficiency should all be optimized while realizing quantum photonic circuits. Although much effort is being devoted to improving the external source coupling efficiency [16; 17], such approaches that aim at probing individual devices on a chip do not allow for highly complex circuits. A scalable alternative is to create on-chip sources that are directly integrated into the passive waveguide network [13; 18]. Resonance fluorescence (RF) from QD coupled into single-mode waveguide has been reported [19]. More approaches are also demonstrated to integrate a quantum emitter with on-chip beam splitters [20; 21; 22]. For the latest research, the control of chiral effects in deterministically fabricated QD-waveguide systems and Purcell-enhanced single-photon source based on a quantum dot coupled to a robust on-chip integrated resonator have been reported [23; 24]. In this paper, we designed and implemented an on-chip single photon source based on a semiconductor III-V quantum dot, which is directly coupled into the waveguide. Via output couplers at both ends of the waveguide, non-classical light is extracted. The quantum dot membrane that contains emitters is released from bulk crystal and picked up by a new substrate such as SiO\({}_{2}\). Then, the waveguide and output coupler structures are directly made from the QD membrane. This greatly reduces the difficulty of the fabrication process for integrating a single source into an on-chip circuit. The on-chip single photon source is directly integrated into the passive waveguides, which will dramatically improve the source coupling efficiency.