Pryroda Engineering

AIXTRON and Semileds report first success with UHB blue LEDs on 6-inch sapphire wafers

Aachen/Germany, April 30, 2009 – A collaboration between AIXTRON and Semileds has resulted in the successful fabrication of GaN-based blue LED chips on 6-inch sapphire wafers. Not only were optical results encouraging but also the process is sufficiently close to production compatibility that the company should soon be able to reap the rewards from larger wafers.

…Specifically, the LED structure was deposited on a 1000 µm thick 6-inch sapphire substrate using an AIX 2800G4 HT MOCVD reactor in the 6×6-inch configuration.
Dr. Chuong Tran, President and COO of Semileds, comments on the results: “Brightness and efficiency are encouraging even though we are only a small step away from our existing and mature 4-inch sapphire process…”

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“One of the contributing factors to yield enhancement is the significantly reduced edge area compared to the area equivalent of nine 2-inch wafers.”

Our question:
- What is the relative yield enhancement between 2″ and 6″ wafers?

Dr. Christian Geng, General Manager Greater China of AIXTRON adds: “The process obviously works from A to Z. I expect that once the price of a 6-inch substrate becomes competitive many of our customers will convert their AIX 2800G4 HT systems from 42×2-inch to 6×6-inch configuration since it merely requires the exchange of the so-called Satellite Disks.”

Another question:
- What will be a competitive price for 6″ wafer?

Source: Axitron, an equipment manufacturer with strong routs in Germany.