The effect of annealing on resistivity of low pressure chemical vapor deposited titanium diboride

Abstract

The correlation between the resistivity of TiB2 and the chemical vapor deposition parameters and subsequent annealing temperature have been studied. The films deposited from TiCl4 and B2H6 above 600 °C are found to be nearly stoichiometric TiB2 with a resistivity of 250 μΩ cm±20%, while those deposited below 600 °C are found to contain excess boron, and exhibit a higher resistivity. The resistivity of the films is observed to be independent of thickness in the thickness range from 15 to 550 nm. After high-temperature rapid thermal annealing (≳1000 °C), the resistivity is reduced to as low as 36 μΩ cm. The grain size in annealed films increases exponentially with temperature. The conductivity and the Hall mobility of the samples increase linearly with the grain size. The activation energy of grain growth, conductivity, and Hall mobility was found to be the same, 1.6–1.7 eV. From these results, it is evident that the carrier mobility of TiB2 is dominated by grain boundary scattering. The lower limit for resistivity of chemical vapor deposited TiB2 films is expected to be attainable only after annealing at temperatures approaching 1300 °C.

Effect of volume fraction of reinforcement phase on mechanical behavior of ultra-high-temperature composite consisting of iron matrix and TiB2 particulates

“…8–10 Recently, TiB 2 has received much attention for being used in microelectronics, electrodes, optical mirrors, cutting tools, wear and erosion resistant components, photovoltaic cells, and chemical barriers. 11–24 Recently, Bonnet et al. suggested TiB 2 as the best possible reinforcement for composites used for applications requiring high specific strength in materials.…”

Nano and Nanocomposite Superhard Coatings of Silicon Carbonitride and Titanium Diboride by Magnetron Sputtering

“…All these combinations of properties suggest the enormous potential of TiB 2 thin films in wear, abrasion resistance, and oxidation‐resistant applications. Because of its high electrical conductivity, it also has the potential for use as interconnects for semiconductor applications 22 . Nanosize‐grained coatings are expected to possess excellent tribological properties (low friction coefficient with low wear rates) of TiB 2 , indicating their potential as a hard solid lubricant wear‐resistant coating on different industrial parts as well as on surgical tools.…”

Titanium Diboride Thin Films by Low-Temperature Chemical Vapor Deposition from the Single Source Precursor Ti(BH4)3(1,2-dimethoxyethane)

“…In addition, it has a low electrical resistivity of 6 µΩ‚cm for single crystal and 10 µΩ‚cm for polycrystalline forms. 2 TiB 2 is an attractive material for use as a hard coating for cutting tools, 3 as an electrode 4 and a diffusion barrier material 5,6 in microelectronics, and as a substrate to grow superconducting MgB 2 thin films. 7 Thin films of TiB 2 have been deposited both by sputtering [8][9][10] and chemical vapor deposition (CVD) routes.…”