A middle-1X nm NAND flash memory cell (M1X-NAND) with highly manufacturable integration technologies

A middle-1x nm design rule multi-level NAND flash memory cell (M1X-NAND) has been successfully developed for the first time. 1) QSPT (Quad Spacer Patterning Technology) of ArF immersion lithography is used for patterning mid-1x nm rule wordline (WL). In order to achieve high performance and reliability, several integration technologies are adopted, such as 2) advanced WL air-gap process, 3) floating gate slimming process, and 4) optimized junction formation scheme. And also, by using 5) new N±1 WL Vpass scheme during programming, charge loss and program speed are greatly improved. As a result, mid-1x nm design rule NAND flash memories has been successfully realized.