Free-Standing & Bulk GaN Substrates for Laser Diode, LED and Power Electronics
LED applications will become the driving force of the bulk GaN market, surpassing established laser diode (LD) and emerging power electronics segments. However, major changes could occur if 4″ bulk GaN price gets below the breakeven price.
In either a cautious or a more aggressive scenario, LED applications will certainly be the key drivers for the bulk GaN market
There is no doubt that LED technology will take market share over the traditional lamp and tube business. The recent announcements from LED makers (> 150 lm/W now in production) are proving that the performance roadmap is in line with expectations: LED does as well and even better than traditional bulbs and tubes.
Native bulk GaN emerges as an alternative to sapphire or silicon, allowing further improvement of LED performance. Despite potential performance benefits for UHB- LEDs, massive adoption of GaN wafers remains hypothetical. Taking into account the historical price reductions of bulk GaN substrates, a base scenario outlines where the GaN on GaN LEDs will be limited only to niche markets. If the GaN industry succeeds in replying to the cost pressure from LED makers and the price of 4″ GaN wafers falls below the breakeven price, a more significant adoption could be forecast. We see an about three times difference in terms of market volume for LED manufacturing between the two scenarios.
Blu-ray applications now represent the largest market for blue LD applications. This market will increase in the short term with the arrival of the new generation game stations. However, we believe that this growth will not persist, as more and more people will play games and watch movies online instead.
Despite the recent rapid development of blue and green laser diodes, we see two scenarios for the adoption of GaN based laser diodes for the emerging projector market. The price of LDs is the essential factor to consider.
Combining all applications, the demand for 2″ GaN substrates will be more than 2 times higher in the aggressive scenario than in the base scenario In the best case, the demand would keep relatively stable until 2020.
In R&D, non polar and semi polar substrates have been proposed for LD manufacturing. In principle, the semi polar approach seems to be the most promising in terms of device performance. In practice, c-plane based devices still have better performance.