Indium Phosphide

Overview

Indium Phosphide (InP) is a well-established material for discrete optoelectronic components. It has been used commercially for several decades for laser diodes and photodetectors operating in the O- and C- bands, particularly for optical fiber communications. Recently, InP is becoming increasingly important as a generic platform for photonic integrated circuits. This is due to its ability to enable monolithic integration of all active components, especially lasers and semiconductor optical amplifiers, as well as high-speed photodetectors and modulators, together with waveguides and other passive components.

Characteristics

InP has a direct bandgap with energy corresponding to telecom wavelengths and high electron mobility, which makes it an ideal platform for high-power light sources and high-speed modulators for long-haul and high data rate optical links.

In combination with other monolithically integrated active and passive functionalities, it is promising for a larger scale integration of PICs with many components on a single chip, such as multi-channel coherent transmitters and receivers for optical communications. However, InP waveguides have higher propagation losses than SOI or SiN waveguides.

The larger waveguide cross-section and lower refractive index contrast (about 3.3) of InP waveguides compared to SOI result in larger bend radii of 100 µm or more and, hence, a larger footprint in a PIC.

In applications where monolithic integration is not crucial, InP active components can be heterogeneously or hybridly integrated with more compact passive SOI or SiN PICs instead by means of bonding, edge coupling or micro-transfer printing.

Applications

Besides applications in telecom and datacom, the InP platform can be used for automotive LiDAR and sensing, such as distributed sensing, and potentially in consumer electronics or wearable medical devices. When co-integrated with other PIC platforms, it can be used for integrated lasers with improved characteristics, for applications in metrology or sensing.

Bring your PIC project to life

At Epiphany Design, we work with all PIC material platforms and always advise our customers on the best choice for their particular applications. When it comes to indium phosphide photonics, we know how to make the most of its strengths to create solutions across a wide range of use-cases. We specialize in PIC Design, but also provide support at all stages of PIC development when needed.