Korean media reported on the 3rd that South Korean GaN technology developer Soft-EPi announced on the 2nd that it has successfully developed and released red GaN epitaxial wafers, which can improve the performance of Micro LEDs. It is said that this is the first time in Korea.
It is well known in the industry that AlGaInP materials are generally used for the preparation of red-light Micro LEDs. However, due to the limitation of physical properties, the efficiency of red-light Micro LEDs prepared based on AlGaInP materials will be significantly reduced as the chip size shrinks, and in the mass transfer process, AlGaInP materials The flaws are also very obvious.
Specifically, the AlGaInP material has a high surface recombination rate. If this problem is solved, it will lead to poor temperature characteristics of the LED. At the same time, the AlGaInP material has weak mechanical properties and poor mechanical strength, which will greatly reduce the yield of Micro LED mass transfer. In addition, the high wafer cost will also increase the cost of the Micro LED process.
In contrast, InGaN material has the advantages of adjustable wide band gap, high mechanical stability and short hole diffusion length, and is compatible with InGaN blue and green LEDs, which is conducive to the realization of full-color Micro LEDs. In recent years, it has received extensive attention in the field of Micro LED, and many forces around the world have begun to actively study the application of InGaN-based materials in the field of Micro LED, and Soft-EPi is one of them.
Last year, Soft-EPi successfully produced red LEDs based on GaN (GaN deposited on sapphire substrates), and used the same method to develop blue LEDs and green LEDs on sapphire substrates, which attracted the attention of the industry. More recently, Soft-EPi has focused on improving performance and has decided to launch epitaxial wafers based on red GaN.
Soft-EPi pointed out that due to the high technical difficulty, currently only 4-5 companies in the world can produce GaN-based red LEDs. However, because manufacturers in the field of GaN-based red epitaxial wafers have signed exclusive cooperation agreements with brand manufacturers such as Meta and Google, and there are many difficulties in research and development, Micro LED developers cannot obtain GaN-based red epitaxial wafers.
Soft-EPi has successfully integrated red and green LEDs on the same wafer, and plans to integrate and demonstrate blue LEDs within this year. Next, Soft-EPi plans to supply this product to interested Micro LED developers.
However, the head of the Soft-EPi Research Center said that the efficiency of red GaN epitaxial wafers still needs to be improved, and Soft-EPi will continue to work with customers to improve the performance of products.