The research and product development of 90-nanometer ETOX NOR flash memory using floating gate technology in this project began in 2008, with a total investment of 20.58 million yuan. ETOX technology is the most mainstream technology used in NOR-type flash memory, and about 70% of flash memory uses this technology. NOR-type flash memory is the earliest flash memory, which has the advantages of high reliability and fast random read speed. Its architecture is characterized by its ability to provide high-speed data read performance, so it is regarded as the best choice for store instructions. Not only that, it also has an SRAM interface, which also provides enough address pins for addressing, and can execute program code directly within it. As various consumer electronic digital products, such as smartphones and tablets, have become mainstream products on the market, the status of flash memory has also risen. It is widely used in situations where there are few erase and programming operations and code execution is directly carried out, especially in pure code storage applications, such as computer BIOS firmware, mobile phones, hard drive control memory, etc. In 2008, 90nm technology was the mainstream technology in international flash memory production, mainly monopolized by well-known foreign NOR flash memory suppliers Spansion, Intel, ST, etc. The 90nm ETOX flash memory of this project is the first flash memory in mainland China to adopt the 90nm manufacturing process. Except for SMIC, no company in China had carried out research and development of this technology at that time. The successful development and mass production of this technology has upgraded the flash memory manufacturing technology independently developed by China to 90nm, promoted the technological development of the design industry and packaging and testing industry upstream and downstream of the industrial chain, and filled the domestic gap in this technology field., breaking the situation of foreign monopoly of technology. The project completed research and development in May 2010, and has carried out technological innovation and improvement in device process, model and numerical simulation database. The key technologies that have been broken through include: 1. In terms of device process, through process optimization, a shallow trench isolation structure has been researched and developed. The manufacturing method improves the yield and reliability of the product.  2. Develop a hard mask process to compensate for the impact of excessively thin ArF photoresist on etching, effectively improve the control and uniformity of key size of the device, and improve product yield and product reliability. 3. A complete set of models and numerical simulation databases were successfully established to accelerate the completion of subsequent customer device debugging. It provides convenient and quick services for new customers to quickly verify and design circuits and micro-adjust devices. 4. Effectively improve the mismatch of devices (H/LV MOS, Resistor, etc.). On the basis of maintaining high performance and low loss of low-voltage tubes, high-voltage tubes with sufficient high voltage have also been developed. 5. In terms of product reliability, the process has reached the industry standard of erasing 100,000 times and storing data for ten years, and successfully passed the customer's product test. So far, a total of 13 invention patents have been submitted for this project, 6 of which have been granted invention patents; the remaining 7 are being accepted (1 is a U.S. patent). As of December 2012, the project has a cumulative new output value of 131.34 million yuan and a profit of 21 million yuan. The products are sold to North America, East Asia and domestic markets, with more than 57 varieties. The products of this project are mainly used in various consumer electronics, such as digital TVs/smart TVs, set-top boxes, DVDs, network equipment, PCs and notebooks, servers, mobile devices, mobile phones, mobile network equipment, etc.