Successors to sapphire in the GaN market

摘要

2002 has seen a resurgence of interest in the development of GaN single crystal substrates. The number of companies in the field has grown and they are at last receiving major funding to help them overcome the next hurdles. The impetus behind this lies in the shortcomings of the sapphire-based technologies currently in use. There is still a question mark against the commercial viability of pure GaN wafers when and if they will ever match the market need for low-price materials. It has been six years since the first Ill-nitride violet laser. While such devices are now commercially available from Nichia and have found their way into a growing range of applications, these devices still fall short of the requirements of volume products such as all-digital re-recordable next-generation DVD on both a commercial and technical basis. Each device still costs one hundred times more than a red laser of the same power. This is due in part to the fact that production volume remains tiny and yet their lifetime and stability are far from being good enough.