Evolution of embedded flash memory technology for MCU

Abstract

Embedded flash memory technology has undergone tremendous growth of demands with various performance requirements driven by expanded applications of MCU (Micro Controller Unit) products. High temperature operations with highest reliability for auto-motive applications, very low power embedded EEPROM functions for smart-cards, and ultra low-voltage operations for medical applications are driving factors in developing embedded flash technologies. Together with evolving memory cell technology, resolving performance/power trade-offs by developing dedicated design platforms with optimized eFlash technology, memory interface & bus designs, and the whole chip design methodologies, has realized advanced MCU products line-ups by split-gate MONOS flash technology with a wide range of applied products including auto-motive and security applications. Index Terms-embedded flash memory, split-gate flash memory cell, charge-trapping flash memory cell Embedded Flash Memory -innovation by overall cost reduction CPU RAM Periph.

A 55-nm, 0.86-Volt operation, 75MHz high speed, 96uA/MHz low power, wide voltage supply range 2M-bit split-gate embedded Flash

“…For high-density (2~16Mb) application, a new split-gate cell (ESF3) has been developed in 90nm and 55nm low-power (LP) process at 12-inch FABs, which is expected to cover the wider-spectrum applications. In [1], [2], strong growth either in automotive, industrial and commercial markets is predicted. The split-gate cell has merits of low cost per bit, fast code execution, and a better candidate for automotive application [1], but few papers introduce eFlash design to respond its strong growth and attention [3].…”

Serial RRAM Cell for Secure Bit Concealing

“…The battery is required to avoid the volatility of SRAM memories, at the expense of an increase in cost, complexity, and power consumption. Logic EEPROM/Flash [4][5][6] are based on the floating gate technology and have been successfully deployed in automotive microcontroller units (MCU) and smartcard ICs. However, they are still expensive and require additional masks and process steps in comparison with the standard CMOS technology.…”

A Floating Gate Memory with U-Shape Recessed Channel for Neuromorphic Computing and MCU Applications

“…To reduce peripheral discrete devices and increase applicability, MCU tends to store programs and small amounts of data through embedded non-volatile memory (NVM). Therefore, with the expanding scale of semiconductor devices and the increasing density of transistors, embedded flash memory, as an important branch of flash products, is more and more widely used in the booming MCU market, and its requirement of integration density is higher and higher [1,2,3,4]. With the development of Moore’s law, the traditional horizontal channel embedded flash memory has limited miniaturization capability and encountered the small size effect.…”