Rapid annealing of Au thin films by micron chevron-shaped laser beam scanning toward growth of single-grain crystal

Abstract

A practicable solution to reduce the density of grain boundaries in metal thin films in order to improve their physical properties, and compatibility with nanoscale fabrications still remains a challenge for the thin film industry. We propose an alternative approach to the problem by using micron chevron-shaped laser beam (μCLB) annealing for rapid and selective growth of crystal grains in metal thin films. We investigate the laser annealing of various Au thin films and discuss the mechanisms of grain growth accounting for the microstructure of the Au films and interaction between the Au films and the substrate. The successful growth of single-grain crystal on a 50 nm Au film by μCLB annealing is also demonstrated and further optimization of the process is discussed.

Infinite lateral growth of (001) single crystal strip in Ge film on SiO2 by micro-chevron laser scanning method

“…12) Occurrence probability of TB was then reduced to smaller than 0.3 mm −1 . We also extended this approach to the growth of single crystal strips in Ge, 13) Cu 2 O, 14,15) Au, 16) and Al 17) films. We fabricated top gate (TG) thin film transistors (TFTs) on Si single crystal strips, which exhibited an impressive average electron mobility of 310 cm 2 V −1 s −1 .…”

Characteristics and deviation of low-temperature FD-SOI-MOSFETs using a sputtering SiO2 gate insulator

“…The chevron laser beam was then scanned over the Si film, and a singlecrystal Si strip with a width of approximately 8 μm was produced infinitely in the Si film. In addition to Si, single-crystal strips were produced in Ge, 29) Cu 2 O, 30,31) Al, 32) and Au 33) films. Both top-gate TFTs (TG-TFTs) 26) and bottom-gate TFTs (BG-TFTs) 28) were fabricated on a single-crystal Si strip, and the TG-TFTs demonstrated remarkable characteristics and variations.…”

Water-Immersion Laser-Scanning Annealing for Improving Polycrystalline Au Films

“… 18 , 19 In addition, several material characterization methods were usually used to measure the grain size and the orientation of (111), such as field-emission scanning electron microscopy (FE-SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), and atomic force microscopy. 23 − 25 …”

“…The accuracy of the measure of dielectric constants (permittivity) is usually related to the thickness of the metal film and the adhesion layer. In addition, the Kramers–Kronig (K–K) model is used for the curve-fitting of optical constants or dielectric constants of the metal film, a lossy material, to obey a constraint of the linear causality for the dielectric constants of metal. , In addition, several material characterization methods were usually used to measure the grain size and the orientation of (111), such as field-emission scanning electron microscopy (FE-SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), and atomic force microscopy. − …”