Hanyang University Professor Jaekyung Jung's Team Develops "Vertically Stackable Ternary Logic Device"

A New Paradigm for Overcoming the Limits of Integration Density
Development of Vertically Stackable Ternary Logic Device Technology Based on CMOS Process

Hanyang University announced on June 5 that the research team led by Professor Jaekyung Jung of the Department of Convergence Electronics Engineering has developed a "vertically stackable ternary logic device technology" based on existing CMOS semiconductor process technology.

Professor Jaekyung Jung, Department of Convergence Electronics Engineering, Hanyang University.

Traditional silicon-based semiconductors have improved performance by increasing integration density according to Moore's Law. However, as the spacing between wiring decreases, increased parasitic resistance and capacitance have led to performance degradation and power consumption issues.

As a new paradigm to address these challenges, "ternary logic" technology, which can process three states (0, 1, 2) simultaneously, is gaining attention.

To implement ternary logic, a transistor with the unique conduction property of Negative Differential Transconductance (NDT) is required. However, conventional NDT transistors have faced limitations in compatibility with CMOS processes and large-area integration.

To overcome these limitations, Professor Jung's research team utilized sputtering, one of the CMOS processes. They also applied high-performance p-channel oxide "tellurium oxide (TeOx)" and n-channel oxide "indium gallium tin oxide (IGTO)," both suitable for low-temperature processes.

Through this, the team proposed a technology for realizing a ternary inverter device based on a heterojunction transistor with NDT characteristics. In addition, by optimizing the inverter structure, they achieved three distinct logic states and demonstrated the potential for large-area integration through wafer-scale fabrication.

Professor Jung explained, "This research is significant in that it presents the possibility of overcoming the high integration challenge, which has been considered a limitation in conventional multi-valued logic."

Meanwhile, this research was published online on May 19 in the world-renowned materials science journal "Advanced Functional Materials (IF=18.5)."