Suzhou/China, April 8th, 2022 - Enkris Semiconductor, an expert and pure epi-foundry of GaN wafers, releases its disruptive Full Color GaN® RGB series of products with wafer size up to 300mm for Micro-display industry.

 

GaN-on-Si LEDs show advantages over those grown on other substrates for Micro-LED technology in terms of larger wafer size (200mm–300mm) and better surface quality. Furthermore,  taking advantage of state of the art Si processing in 200mm/300mm FABs,  high performance arrays of tiny(5 µm2) Micro-LED pixels can be fabricated and integrated on Si CMOS driver with high yield. 

 

Near-eye-displays such as augmented reality (AR) and mixed-reality (MR) devices, require high-efficiency, ultra-fine-pitch (<5µm) Red, Green and Blue pixels integrated on the same material platform. InGaN materials can emit light efficiently covering the entire visible spectral range by adjusting the Indium content. Although high efficiency blue and green InGaN-LEDs have been achieved, it is still very challenging to grow high efficiency red LEDs due to the pronounced strain in the active region and the poor crystalline quality resulting from the large lattice mismatch between InGaN QWs and GaN buffers. Enkris Semiconductor has successfully overcome these difficulties by using its patented strain engineering and polarization engineering (Pic. 1 & Pic. 2). By adopting its unique bandgap tuning technology, Enkris expands its GaN-on-Si LED epi-wafer product portfolio to Full Color GaN® RGB series of products (wavelength: 390~650nm) on 200mm Si substrates. 

 

 

Picture 1: Enkris’ Full Color GaN® RGB series of products

 

 

Picture 2: IQE comparison and EL spectra of Full Color GaN® RGB series of products on Si and Sapphire

 

 

Wavelength uniformity is a key factor for Micro-LED display. Enkris’ Full Color GaN® RGB series have excellent wavelength uniformity across 200mm whole wafers (Pic. 3). Moreover, GaN-on-Si Blue LED wafers are available up to 300mm and the wavelength is reasonably good with a  standard deviation of less than 2nm (Pic. 4).

 

 

Picture 3:  Full Color GaN® RGB series 200mm LED WLD mapping

 

 

Picture 4: Enkris’ 300mm GaN-on-Si Blue LED WLD mapping 

 

Enkris Semiconductor also demonstrates RGB micro-LED arrays with pixel size range from 2µm to 50µm, based on Full Color GaN® RGB series of 200mm epi-wafers (Pic. 5 & Pic. 6). Thanks to the high quality epi-wafers, all the pixels can be light up even for each 2µm2 tiny pixel (Array: 100 x 100). This is the key accelerator to the micro-display adoption.

 

            

Picture 5: Enkirs’ 200mm Micro-LED wafer

 

 

(Pixel size: 50µm, 15µm, 5µm, 2µm)

Picture 6: Micro-LED Arrays based on Full Color GaN® RGB series

 

Dr Kai Cheng, Enkris’ founder and CEO comments: “For monolithic integration of micro-LEDs, it is a critical step to integrate all three colors into a single material platform of large size GaN-on-Si. Our Full Color GaN® series products will fulfil the industry’s requirement for AR/MR systems. In addition, the GaN-on-Si wafer size can be scaled up to 300mm and we presented 1200V 300mm GaN-on-Si platform in Sept., 2021. The new platform of 300mm GaN-on-Si LED will show great promise in heterogeneous integration of GaN optical devices, GaN electronic devices and Si devices. Enkris is now able to supply true RGB GaN-on-Si epitaxial solution for display industry and empower the development of full color micro-display, and embrace the era of Metavere.

 

Enkris’s Full Color GaN® series of products are available on both GaN-on-Si and GaN-on-Sapphire wafers.

 

Acknowledgment

Enkris semiconductor would like to express its gratitude to Raysolve, for the support and convenience during the device validation and evaluation of GaN epitaxial materials.