Japan announced the development of a GaN semiconductor thin film element can be stripped from sapphire substrate technology

The day before, NTT (NTT) announced the development of GaN can be easily stripped by LED from sapphire substrate (potassium nitride) process semiconductor thin film element.

The technology can be made with low cost for the thickness of thin GaN semiconductor thin film 2 m, is expected to expand the application range of GaN semiconductor thin film materials, such as visible light through the efficient absorption of solar ultraviolet radiation only, and the thickness of 200 m thin LED. In addition, by increasing the area of the stripped thin film element, it is possible to form a thin film element with a new function in the upper layer of the thin film element.

According to NTT introduction, in the sapphire substrate stacked, processing GaN semiconductor thin film components, used to make the device, the thickness of the substrate must be around 0.5mm. Therefore, the world is in the process of how to process the film components from the substrate completely stripped down, and paste on other substrates technology. Based on the study of BN (boron nitride) with graphite with the same lamellar crystalline structure, the using based Institute of physical properties of NTT has developed the MeTRe method (Mec hanical Transfer a RELease layer). The MeTRe method can keep intact crystallization after stripping surface, so it can be necessary to save the previously proposed transfer method, in the flat surface after stripping process. Moreover, the use of MeTRe stripping does not require large equipment and chemicals, is expected to significantly reduce manufacturing time and manufacturing costs.

As one of the key points in the development of high quality laminated BN films, the MeTRe method has a high quality BN film with a layered crystalline structure on the substrate, and a high quality thin film element is laminated on the substrate. In this structure, BN thin films were grown in between the substrate and the film element plays the same role as the stamp perforations, can be easily stripped and pasted into other substrate. According to NTT, this is the best film forming conditions, the crystallization of the direction of a unified high-quality BN film lamination.

The 21 main points of development in the layered BN film on high quality GaN thin film laminated element, the first development technology in different layered BN film stacked on the crystal structure of AlxGa1-xN (AlGaN) or AlN (AlN) as a buffer layer, and then stacked GaN thin film element. On the layered BN film, the GaN with wurtzite structure is directly stacked, so it is very difficult because of the different crystal structure. The AlxGa1-xN and AlN with Al have good wettability with the substrate, which is widely used in the multilayer substrate. This kind of material can be used as the buffer layer between the layered BN thin film and GaN, and the high quality thin film element can be laminated and formed regardless of the crystal structure.