Development of an Epitaxial Growth Technique Using III-V on a Si Platform for Heterogeneous Integration of Membrane Photonic Devices on Si

Abstract

The rapid increase in total transmission capacity within and between data centers requires the construction of low-cost, high-capacity optical transmitters. Since a tremendous number of transmitters are required, photonic integrated circuits (PICs) using Si photonics technology enabling the integration of various functional devices on a single chip is a promising solution. A limitation of a Si-based PIC is the lack of an efficient light source due to the indirect bandgap of Si; therefore, hybrid integration technology of III-V semiconductor lasers on Si is desirable. The major challenges are that heterogeneous integration of III-V materials on Si induces the formation of dislocation at high process temperature; thus, the epitaxial regrowth process is difficult to apply. This paper reviews the evaluations conducted on our epitaxial growth technique using a directly bonded III-V membrane layer on a Si substrate. This technique enables epitaxial growth without the fundamental difficulties associated with lattice mismatch or anti-phase boundaries. In addition, crystal degradation correlating with the difference in thermal expansion is eliminated by keeping the total III-V layer thickness thinner than ~350 nm. As a result, various III-V photonic-device-fabrication technologies, such as buried regrowth, butt-joint regrowth, and selective area growth, can be applicable on the Si-photonics platform. We demonstrated the growth of indium-gallium-aluminum arsenide (InGaAlAs) multi-quantum wells (MQWs) and fabrication of lasers that exhibit >25 Gbit/s direct modulation with low energy cost. In addition, selective-area growth that enables the full O-band bandgap control of the MQW layer over the 150-nm range was demonstrated. We also fabricated indium-gallium-arsenide phosphide (InGaAsP) based phase modulators integrated with a distributed feedback laser. Therefore, the directly bonded III-V-on-Si substrate platform paves the way to manufacturing hybrid PICs for future data-center networks.

Freestanding Membranes for Unique Functionality in Electronics

“…Epitaxy can be performed in diverse ways with abundant characteristics for developing high-performance electronics, optoelectronics applications, and multifunctional sensors. − The concept of constructing various semiconductor materials on a single substrate has been a significant subject of research for many years. , Conventionally, single-crystalline epitaxial multilayers are primarily grown on a lattice-matched substrate, for instance, InGaN/GaN on a GaN substrate . However, the ever-increasing demand for advanced optoelectronic integrated circuits has fueled the need to combine materials with different lattice constants.…”

Single crystalline Ge thin film growth on c-plane sapphire substrates by molecular beam epitaxy (MBE)

“…As a result, research efforts are now focusing on integrating photonic devices, monolithically fabricated on a silicon photonic platform. 1,2 The heart of this approach is the photonic chip, along with fiber arrays to couple light in and out of the chip. However, since silicon is an indirect bandgap material, the silicon chip is without an integrated laser source.…”

Thickness Effect on the Solid-State Reaction of a Ni/GaAs System

“…With the exponential development of photonics, optoelectronics, photovoltaics, and microelectronics, the attention of researchers has turned to new materials that are more efficient than silicon, such as III-V semiconductors [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. III-V semiconductors have promising physical and electrical properties such as direct band gap and high charge carrier mobility [ 8 , 9 , 10 , 11 ].…”