Photonics is the physical science of generating, detecting and manipulating light. The use of photonics technology enables much faster transmission of data than electrical signals sent through copper wire. Optical communications and sensing constitute the largest demand for photonics devices, led by data communications and telecommunications, both of which require increasingly speedy networks.
Data centers dominate growth in the datacom space, with “all things connected” driving more traffic through them, including hyperscale data centers built to accommodate massive cloud usage. In the telecom market, 5G networks are the primary driver. The 5G backbone comprises both wireless and fiber-optic communication, which is necessary for data exchanges between cell towers, over the internet, and between macrocells on city blocks.
High-performance, reliable photonics devices with excellent wavelength uniformity are essential for fast transmission of optical signals. Examples of these devices include compound semiconductors such as indium phosphide (InP) edge emitting lasers (EELs) at 1.3/1.5-micron wavelengths; gallium arsenide vertical-cavity surface emitting lasers (GaAs VCSELs) at 850nm; and photodetectors.
Metal organic chemical vapor deposition (MOCVD) plays a key role in bringing these photonics devices to market. A well-designed MOCVD reactor allows development of high-performance, uniform optical devices, with very low wavelength variation across wafers and runs, at high yields.
Photonics devices require high power conversion efficiency (PCE) and reliability. MOCVD impacts two key aspects of PCE: external efficiency and series resistance. Achieving high external efficiency requires quality materials, sharp interfaces between compound semiconductor layers, and no background doping – all of which is enabled by high-performance MOCVD processes.
Realizing low series resistance also requires high interface sharpness, as well as low memory effect. When you switch gas sources and dopant materials between layers, the MOCVD reactor should fully evacuate the prior material so that new layers can be grown on top of each other with no overlap, which hinders device performance.
Veeco supports the photonics market with our line of MOCVD platforms: EPIK® 868 for LED production; Propel™ GaN-based systems for power, 5G RF, CMOS and photonics devices; and Lumina®, our arsenide phosphide (AsP)-based system, designed to create high-performance next-generation photonics devices in high volumes for datacom/telecom applications. These include mini and micro LEDs, VCSELs, and EELs, which require thermal stability and run-to-run repeatability for high production continuity and yield.
At the heart of our MOCVD platforms is our TurboDisc® reactor, created to grow epitaxial structures with the industry’s highest uniformity and lowest defectivity. Designed for rapid development and a fast HVM ramp, the TurboDisc technology delivers uniform film growth (within wafer, wafer to wafer, and run to run).
The reactor’s vertical injection and high-speed rotating disc together work to quickly ‘pull’ gas down, and the chamber is then evacuated by a vacuum pump through exhaust below the wafer carrier. This happens quickly, so gas resides very briefly in the chamber, without lingering or coating areas outside the deposition plane. The resulting materials feature sharp interfaces with no background doping or memory effect, for fast, high-performing photonics devices.
Lumina’s typical recipe time is about 4.5 hours for VCSELs and 2.5 hours for thinner EELs or micro LEDs. Uptime averages more than 300 runs between preventive maintenance (PM) cycles, which can be performed in less than one shift (about four hours) with zero recovery time – after one quick bake, it can go back into production, with no post-PM conditioning or recipe tuning.
If you need advanced MOCVD technology for your photonics applications, contact Veeco today