Equipment Suppliers Brace For GaN Market Explosion - including Atomic Layer Etch (ALE)

According to a recent article in Semiengineering Power Electronics and RF will drive volume for equipment suppliers, with many new uses underway. According to industry experts interviewed, also ALD and ALE will benefit

“Through an ongoing development program, Lam Research has been establishing a suite of enabling process solutions for GaN semiconductor device fabrication,” said David Haynes, vice president of specialty technologies in Lam Research’s Customer Support Business Group. 

“Key to these capabilities is an atomic layer etch-based process that can provide ultra-low damage, atomic scale precision etching of GaN and related materials. The new, optimized processes can reduce the post etch sheet resistance of the as-etched GaN/AlGaN [aluminum gallium nitride] whilst the surface roughness of the etched material remains comparable to that of the incoming epitaxial layers. Such high-precision, low-damage etch capabilities are critical to the formation of p-GaN or recessed gate high electron mobility transistor (HEMT) architectures used to fabricate normally off GaN devices for power electronics applications.”

Lam’s Kiyo45 reactive ion etch (RIE) tool offering ALE processes of GaN and SiC materials Source: Lam Research

According to the article, Lam has developed proprietary solutions to speed up the ALE process and its ALE chambers can be used in both RF and power GaN fabrication.

Lam sees GaN on SiC RF devices as well established and will remain very important for high power applications in telecommunications infrastructure and defense. Fast development of GaN-on-Si epitaxy will move towards high volume applications for consumer products according to Haynes and explained further: “These will evolve alongside GaN-on-Si power devices that share many of the same process challenges. Today, most GaN-on-SiC RF devices are still made on 150mm or even 100mm wafers. The opportunity for GaN-on-Si devices to be readily processed on 200mm and in the future 300mm wafers, as well as the potential to use complementary metal-oxide semiconductor (CMOS) foundry capacity and even develop integrated solutions with CMOS, will all be key drivers for this transition.”

The Lam Research was early in high volume manufacturing with ALE (2016 BALD Engineering - Born in Finland, Born to ALD: Lam Research - New Atomic Layer Etching Capability Enables Continued Device Scaling) ALE chambers are now also part of their Kyo45 reactive ion etch product platform and offers (lamreserch.com):

• Superior uniformity and repeatability enabled by a symmetrical chamber design, industry-leading electrostatic chuck technology, and independent process tuning features
• High productivity with low defectivity on multi-film stacks enabled by in-situ etch capability, continuous plasma, and advanced waferless auto-clean technology
• Improved critical dimension uniformity using proprietary Hydra® technology that corrects for incoming patterning variability
• Corvus® plasma sheath tuning for maximum yield of wafer-edge dies
• Atomic-scale variability control with production-worthy throughput enabled by plasma-enhanced ALE capability
• Upgradable products for low cost of ownership over several device generations

Sources: 

- Equipment Suppliers Brace For GaN Market Explosion

Equipment Suppliers Brace For GaN Market Explosion (semiengineering.com)

- Lam Research www.lamresearch.com