New Functional Materials for Semiconductor Devices

MSIM (Metal-Semiconductor-Insulator-Metal) Diode 

Conventional diodes have made a major contribution to most electronics industries. Rectifying diodes not only allow current to flow when needed, but also make the device structurally affordable. In the case of using an oxide semiconductor, it is difficult to make a P-N diode due to the difficulty of developing a p-type semiconductor, and in the case of the schottky type, there is a problem that off leakage flows because it is difficult to actually make a schottky contact with a metal. In order to solve these problems, our lab is investigating diode structures with insulating layers, and is working on high rectification characteristics, low off leakage current, and thin and transparent next generation diode arrays. In general, oxide insulating layers have a large bandgap, creating an environment in which electrons cannot flow. By inserting the oxide semiconductor in the middle, we have fabricated a diode that can flow current even at a certain thickness without tunneling. It is expected to be used in next generation industry through thin, transparent and high rectification diode.

Ferroelectric Materials

Neuromorphic Devices & Inter Metal Dielectrics

1. Neuromorphic Devices

Conventional semiconductor devices are developed based on von Neumann computing system. However, due to the inherent problems of von Neumann's architecture; the limits of satisfying Moore's law were reached. On the other hand, human brain has huge advantages of handling complex problems. For example, the brain has good energy efficiency compared to von Neumann’s architecture and it can handle logic and memory in parallel. These kinds of reasons, Brain-liked system called ‘Neuromorphic System’ is considered as a next generation computing system. To implement neuromorphic system, artificial neuron and synapse devices that mimic the brain are needed; we research about these artificial devices. Especially, we focus on Synaptic Thin Film Transistors (Synaptic TFTs). Consider Gate as pre-synapse, Source & Drain and Active layer as post-synapse and conductance of the channel as synaptic weight. Synaptic TFTs operate in such a way that a change in the conductance when pulse voltage is applied to the electrode. In this way, TFT mimics the synaptic plasticities that occur in the real human brain, which become a mechanism of both memory and logic. Our team has advanced technologies in TFTs with Oxide semiconductor. We have applied these advanced technologies to the Display field; from now on, we will combine them with Semiconductor field to implement neuromorphic with low energy consumption with various operating mechanisms.

2. Inter Metal Dielectrics

In the recent years, micro-electronic technologies have a high demand for inter-metal-dielectric (IMD) layers with a extremely low dielectric constant. These materials are expected to play a crucial role in the future generation of IC devices (VLSI/UISI and high speed IC packaging). Besides their low dielectric constants, these materials exhibit excellent physical properties such as good processability, high mechanical strength, high thermal and environmental stability, low thermal expansion, low current leakage, low moisture absorption, and corrosion resistant. We will investigate the morphology, mechanical and electrical properties of low-k films (SiCOH) grown by PECVD method. This study will provide the applicability of low-k films for inter-metal-dielectric (IMD) layers to replace conventional SiO2.

대전광역시 유성구 대학로 291 (구성동373-1) 한국과학기술원(KAIST) 4405호

Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejeon,

305-701 Rep. of KOREA

TEL : +82-42-350-3356 | FAX : +82-42-350-3310 

Designed by Wixweb