Oxide semiconductor of select transistor for memory devices

Amorphous metal oxide semiconductor like Indium-Gallium-Zinc-Oxide (IGZO) is the most commonly used oxide material in display application due to their field-effect mobility, good uniformity over large glass substrates sizes and low temperature process.Besides driving innovative thin-film transistors for display applications, IGZO is also seen as a strong candidate for replacing silicon in some architectures, helping the semiconductor industry to boost the scaling by placing the transistors in the Back-End-Of-Line of a chip rather than in the periphery. For example, thanks to its extremely low leakage current and its relatively good carrier mobility, IGZO TFT used as selector can make DRAM memories more power efficient while maintaining the data writing and reading at very high speed. In addition, channel material IGZO can be formed at a relatively low temperature, making it conducive for fabrication in stack array. Integration of such material in DRAM cell architecture opens up the possibility of 3D DRAM integration, which helps to continue the DRAM scaling roadmap. Our goal is to explore new schemes and improved material processing in order for IGZO devices to become practical in DRAM application.