MOVPE and its future production challenges

Abstract

III-V Compound Semiconductors (CS) such as Gallium Arsenide (GaAs), Indium Phosphide (InP) and more latterly, Gallium Nitride (GaN) are critical Key Enabling Technologies, fundamentally underpinning several recent major technology revolutions. Two major current and likely-future markets within the burgeoning photonics industry ($7 billion) are 3D imaging and sensing and LIDAR applications, with high predicted market growth. Datacom and industrial markets add considerable further momentum to this market growth. Evidence of such expansion is provided in the manufacturing of VCSEL-based devices, which have in recent years, entered a rapid growth phase. For the mass-manufacturing of for example, GaAs/AlGaAs-based VCSEL MOVPE epitaxy, many areas require addressing in key underlying R&D, such as cost-reduction and in thickness and wavelength uniformity. In addition, scalability, (e.g. to 150 mm wafers), automation and in-situ process control will impact yield and throughput improvements.We will demonstrate the preparations for mass-manufacturing, through improvements implemented across the evolution of the VCSEL epiwafers from smaller diameters, through 100 mm and on to 150 mm wafers. More recently however, further developments have led to even larger diameter VCSEL wafer epitaxy, on both GaAs and Ge 200 mm substrates. Challenges in growing on such large diameter wafers will be presented from the epitaxy (layer uniformity and wafer bow) and device fabrication perspective. We will demonstrate how these improvements impact on the manufacturing readiness of production VCSEL wafers.