Flip-Chip Integration of InP to SiN Photonic Integrated Circuits

Abstract

We present our hybrid InP to SiN TriPleX integration interface with a novel alignment technique and its application to complex photonic integrated circuits. The integration interface comprises vertical alignment stops, which simplify the alignment process and allow for array integration with the same simplicity as for single dies. Horizontal alignment is carried out by utilizing optical backscatter reflectometry to get an active feedback signal without the need to operate the chip. Thus, typical contacting limitations of active flip-chip alignment are overcome. By using this method, we demonstrate the integration of InP DFB lasers with more than 60 mW of optical power coupled to a SiN waveguide with an averaged coupling loss of -2.1 dB. The hybrid integration process is demonstrated for single dies as well as full arrays. We evaluate the feasibility of the assembly process for complex photonic integrated circuits by integrating an InP gain chip to a SiN TriPleX external cavity. The process proves to be well suited and allows monitoring chip quality during assembly. A fully functional hybrid integrated tunable laser is fabricated, which is capable of full C-band tuning with optical output power of up to 60 mW.

CORNERSTONE’s Silicon Photonics Rapid Prototyping Platforms: Current Status and Future Outlook

“…This is often mitigated using a mode-matching waveguide between the III/V and the SiN waveguides made by a material with an intermediate refractive index waveguide, such as silicon or polymer. Examples of integration of III/V devices on a SiN platform are reported in the literature for both flip-chip bonding [183][184][185] and transfer printing [186][187][188] with an insertion loss as low as 2.1 dB.…”

PLC-Based Arrayed Waveguide Grating Design for Fiber Bragg Grating Interrogation System

“…Fiber Bragg grating (FBG) [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ] has become one of the hottest areas of research in the field of optical sensing in recent years, due to its widespread use in aerospace, deep-sea exploration, environmental monitoring, and other industries as an “electronic eye” to monitor temperature, strain, concentration, and other changes in the state of the external environment. To demodulate the wavelength of FBG and obtain the wavelength encoding temperature or pressure variation of FBG, researchers [ 9 ] cleverly combined photonic integrated circuit (PIC) [ 10 , 11 , 12 , 13 , 14 ] technology and FBG interrogation technology in 2004 to create an FBG interrogation system based on PIC technology. A PIC-based interrogation system provides exceptional benefits in the miniaturization and integration of FBG interrogators, as well as a compact structure and low power consumption, while maintaining high accuracy and resolution.…”

On-chip photonics and optoelectronics with a van der Waals material dielectric platform

“…Photonic integrated circuits (PICs) have attracted considerable research interest during the last few decades owing to their broad bandwidth, high operation speed, and power efficiency, promising for various applications, such as data processing, [1][2][3][4][5] sensing, 6,7 and inter-chip communications. [8][9][10] However, to achieve such a heterogeneous photonic system, light sources, optical modulators, and photodetectors need to be ideally integrated onto the same chip, which remains a formidable challenge for the existing material platforms, including silicon on insulator (SOI), 11,12 silicon nitride (Si 3 N 4 ), 13,14 indium phosphide (InP), 15,16 lithium niobate on insulator (LNOI), 17,18 etc. For example, SOI and Si 3 N 4 are the most developed siliconbased material platforms for PICs.…”

“…20,21 Moreover, the hybrid integration of silicon and III/V materials or germanium is also challenging because of lattice mismatch and thermal expansion issues. 9,22 Apart from silicon, InP is another widely explored photonic platform that exhibits excellent performance in active applications, 15,16 but InP is not compatible with CMOS technology, which has become the obstacle that prevents further commercialisation. 23 LNOI is a revolutionary material platform, possessing attractive material properties (e.g., an ultrabroad low-loss transparency window, high second-order optical nonlinearity, and high electro-optical coefficient) 24 that have led to various competitive on-chip devices (e.g., optical modulators 18,25 ).…”