The Soitec Group, manufacturer of silicon-on-insulator (SOI) wafers and other engineered substrates for the semiconductor manufacturing industry, has announced a technology breakthrough using its proprietary Smart Cut™ layer-transfer and wafer-bonding technology.
The company has generated the world’s first single-crystal, thin-film gallium nitride (GaN)-on-insulator substrate—representing a critical step forward in enabling the development of high-performance blue and white light-emitting diodes (LEDs), as well as for improving current and future device performance in radio-frequency (RF) and discrete power applications.
This key milestone was achieved in close collaboration with Picogiga International, a Soitec Group division focused on the development and manufacture of compound semiconductor material solutions, and took place at the Smart Cut Enabling Application Laboratory (SCEALAB). A joint technology development program between the Soitec Group and French research consortium, CEA-Leti, SCEALAB was established to develop new, experimental composite substrates. Soitec’s Smart Cut technology was used by the research team to split and transfer a thin layer of GaN from a high-quality GaN donor wafer onto a carrier wafer—generating a single crystal GaN-on-insulator substrate.
According to Carlos Mazuré, the Soitec Group’s chief technical officer, “This research was performed in very close collaboration with our III-Vs material division, Picogiga International, whose plans to industrialize the new technology are a key component of Soitec’s strategy to extend its technology-development efforts by combining Smart Cut with Picogiga’s epitaxial technology. Leveraging multiple technologies internally is essential to our ability to provide the compound material world with fully engineered substrate solutions, and enables us to leverage Smart Cut as a ‘tool box’ to engineer new substrates beyond silicon.”
Today, the GaN development process is based on growing epitaxial layers of GaN on bulk substrates, such as silicon, silicon carbide and sapphire. RF power devices and high-volume market blue and white LEDs will experience technical limitations in terms of power or brightness that require new technology solutions. By creating GaN-on-insulator substrates with high-quality GaN topsides, Soitec provides the industry with a breakthrough solution to enhance the quality and performance of the active epitaxial GaN layers. Smart Cut provides the capability to optimize the substrate’s mechanical and thermal properties — independent of the topside active layer — and is therefore the best suited to become the industrial standard for cost effective, volume manufacturing of GaN-based wafers.