Professor Hyungkyun CHO’s research team (New Materials Engineering) announced that they discovered a method to miniaturize and expand memory capacity by developing variable resistance memory device.This research was published online at the world renowned journal ACS Nano (IF=13.709).

The research team was able to create amorphous oxide thin film using metal precursor and was successful in developing and proving the stability of ReRAM. In this process the team was able to newly prove the mechanism of memory devices. They also developed a device that can expand the degree of integration of the memory.

The world is now entering the era of 5G and the role of memory is becoming greater than ever. The ReRAM is the memory of next generation that can replace the DRAM and NAND-FLASH.

An ideal memory for semiconductors has uniformity, fast read/writing speed, random access, low cost, 3D expandability, nonvolatile, strong durability, stable in different temperature and provide multiple states. 

The research team used the electrochemical method to check the possibility of synthesizing devices. They argued that the electrochemical process can efficiently control OH- (hydroxyl ion) and the roughness of the surface. The density of OH- on the surface of electrode is an important factor determining the growth rate of thin film. They have successfully synthesized oxide thin later with nano particle and applied it in the memory device.

[Figure 1] Evaluating performance of ReRAM: a. uniformity b. durability c. stability

The ReRAM is known to increase conductivity by creating vacant oxygen inside the basic material. However, this research newly proved that it acts as a bridge that enables the transmission of electron.

[Figure 2] Mimetic diagram of Nps-Cu2O formation and conductible bridge of ReRAM using transmission electron microscope