Yoshikazu Ibara

Behavior of TiN and Ti Barrier Metals in Al‐Barrier‐Al Via Hole Metallization

The behavior of TiN and Ti barrier metals in Al-barrier-Al via structures was investigated. When a reactive-sputtered TiN film is deposited onto an Al-1 weight percent (w/o) Si-0.5 w/o Cu surface, AlN is formed at the TiN/Al interface due to the reaction of N 2 to Al, and causes an increase in via contact resistance. To suppress the increase in via contact resistance, it is crucial to interpose a Ti buffer layer at the TiN/Al interface

Application of cathodoluminescence to SiGe epitaxial process control

A new in-line monitoring method to easily and quickly detect dislocations and defects generated before and after the SiGe epitaxial process is storongly needed. We focus on the cathodoluminescence (CL) method which can directly observe regions within devices and determine dislocations and defects in Si/SiGe/Si double hetero-structures. We systematically investigate the correlation between CL spectra and epitaxial process parameters and demonstrate that CL measurements can detect dislocations and defects that could not be observed by light point defect (LPD) detection or transmission electron microscopy (TEM). The results of evaluation experiments for the proposed CL method indicate that it is effective for the SiGe epitaxial process control.