Vertically Aligned TiS₂ Adhesion Layers via Plasma-Induced Metal Sulfidation and Two-Terminal Device Application.

Area of Science:

• Materials Science
• Nanotechnology
• Semiconductor Physics

Background:

• Semiconductor device scaling requires improved metal-semiconductor contacts to prevent performance degradation from interfacial diffusion and poor adhesion.
• Current methods struggle to mitigate these interfacial issues effectively in advanced nanoelectronic devices.

Purpose of the Study:

• To develop a diffusion barrier and adhesion promoter for robust metal-semiconductor contacts.
• To investigate the efficacy of a vertically aligned TiS2 layer (VATL) synthesized via H2S plasma treatment.

Main Methods:

• Synthesis of VATL using low-temperature H2S plasma treatment.
• Characterization using cross-sectional transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS).
• Evaluation of electrical properties via four-point probe measurements and diode device testing.

Main Results:

• VATL effectively suppressed Ti diffusion and interfacial alloying between Ti and W.
• Enhanced W grain crystallinity and a significant reduction in sheet resistance (from 1510.24 ± 0.92 to 1172.87 ± 3.79 Ω/cm²).
• Diode devices with VATL contacts showed a 17.93-fold increase in ON current without hysteresis, alongside positive stability test results.

Conclusions:

• Vertically aligned TiS2 layers offer a scalable, CMOS-compatible solution for engineering high-performance metal interfaces.
• VATL serves as an effective diffusion barrier and adhesion promoter for next-generation nanoelectronic devices.
• This approach enhances device performance and reliability by addressing critical interfacial challenges.