Effects of Annealing Temperature on Recrystallization Texture and Microstructure Uniformity of High Purity Tantalum

Abstract

One hundred and thirty-five degree clock rolling significantly improves the texture homogeneity of tantalum sheets along the thickness, but a distinctly fragmented substructure is formed within {111} (<111>//normal direction (ND)) and {100} (<100>//ND) deformation grains, which is not suitable to obtain a uniform recrystallization microstructure. Thus, effects of different annealing temperatures on the microstructure and texture heterogeneity of tantalum sheets along the thickness were investigated by X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). Results show that the texture distribution along θ-fiber and γ-fiber is irregular and many large grains with {111} orientation develop during annealing at high temperature. However, low-temperature annealing can not only weaken the texture intensity in the surface and the center layer but also introduce a more uniform grain size distribution. This result can be attributed to the subgrain-nucleation-dominated recrystallization mechanism induced by recovery at low temperature, and moreover, a considerable decline of recrystallization driving force resulting from the release of stored energy in the deformation matrix.

The Effect of Different Annealing Temperatures on Recrystallization Microstructure and Texture of Clock-Rolled Tantalum Plates with Strong Texture Gradient

“…Tantalum (Ta), body-centered-cubic (BCC) structure, is a refractory metal with a series of excellent physical and chemical properties, such as corrosion resistance and good ductility, which makes it an ideal material for microelectronics and sputtering targets [1]. The quality of the sputtered film plays a key role in the semiconductor integrated circuit industry, and the grain size and crystal orientation distribution of the sputtering target have a direct influence on the quality of the sputtered film [2,3]. Different crystal orientations and grain size can lead to the difference in sputtering rates during magnetron sputtering [4].…”

Synthesis of Vacancy-Controlled Copper Iodide Semiconductor for High-Performance p-Type Thin-Film Transistors

“…The surface coverages of the CuI films annealed in air and vacuum atmospheres at various temperatures are shown in Figure S1, where the vacuum-annealed CuI films showed the increased surface area coverage from 67.3 to 87.3% with the increase of the annealing temperature from 100 to 300 °C, whereas the surface area coverage of the air-annealed CuI films decreased with increasing annealing temperature owing to the oxidation of the CuI thin film and the creation of CuO nanoparticles. , The decrease in voids on the vacuum-annealed CuI surface with increasing annealing temperature is similar to a previous report, showing the reduced voids on the CuI surface with increasing substrate temperature in an Ar atmosphere, where it can be ascribed to the increased thermal energy that increases the frequency of the CuI lattice oscillations helping I and Cu to overcome the potential barrier and leave regular sites, generating the I Vac and Cu interstitial defects, which are the most stable defects under Cu-rich condition according to the first-principles calculations . Considering that the release of stored energy can be completed by recrystallization during annealing, the reduction in voids with increasing annealing temperature may be attributed to the increased oscillation, relocation, and recrystallization of the CuI lattice in the vacuum-annealed CuI thin films. The detailed mechanisms need to be explored further.…”

Growth, structural and magnetic properties of Gadolinium oxide (Gd2O3) thin films

“…If the annealing is long enough/high enough temperature continued growth of these new grains (defect free ) may eventually become larger than the original grain size. So one can expect annealing to induce a grain size reduction (initially, incomplete recrystallization) and then an ultimately (possibly) larger grain size [18,19]. And the appearance of vertices indicates that the installation of samples deposited with different annealing temperature is a multi-crystalline structure because there is more than one peak .…”