Veeco Instruments and ALLOS Semiconductors have continued their collaboration in developing GaN-on-Si epitaxy wafer for Micro LED production. The two companies have partnered to demonstrate the reproducibility of ALLOS’ 200 mm GaN-on-Si epitaxy wafer technology on Veeco’s Propel® MOCVD reactor.

“To bring Micro LED technology into production, simply presenting champion values for a single metric is insufficient. It is essential to achieve the whole set of specifications for each wafer with excellent repeatability and yield,” said Peo Hansson, senior vice president and general manager of Veeco’s Compound Semiconductor business unit. “This successful joint effort reaffirms the power of combining Veeco’s superior MOCVD expertise with ALLOS’ GaN-on-Silicon epiwafer technology to provide customers a novel, proven and reliable approach to accelerate Micro LED adoption.”

(Image: ALLOS)

Sorting and binning are standard methods to achieve wavelength consistency for conventional LEDs. But the process is extremely challenging for Micro LEDs as they are too small and numerous to be sorted and binned. Therefore, the uniformity of the epitaxial deposition is even more critical.

The key factor for the commercialization of Micro LED displays is to achieve good emission wavelength uniformity to save the cost and time for testing and sorting individual LED chips. Depending on the application and mass transfer approach, the target requirements of the industry are between +/-1 nm and +/-4 nm bin (min/max) on the epiwafer. Veeco and ALLOS have worked together to further improve the wavelength uniformity of wafer to achieve a standard deviation of 0.85 nm.

“Veeco and ALLOS validated wafer-to-wafer reproducibility with an average wavelength standard deviation for all wafers of 1.21 nm and the peak wavelength within a +/- 0.5 nm range. With these results we made another significant leap towards the +/-1 nm bin goal on an epiwafer,” said Burkhard Slischka, CEO of ALLOS. “Our technology is already available on 200 mm wafer diameter, which enables the use of low-cost and high yield silicon lines for Micro LED chip production. Additionally, we have a clear roadmap to enable 300 mm.”