Electrochemical Growth of Bismuth for X-ray Absorbers

Abstract

Bismuth electroplating and fabrication efforts for its incorporation as an absorber in Superconducting Transition Edge X-ray Sensor devices are summarized. The bismuth films, a few microns thick, are grown using both aqueous and non-aqueous solutions. They are characterized by optical imaging, profilometry, X-ray diffraction, SEM, and by electrical transport (resistivity and Hall Effect) measurements from 30 to 310 K. While aqueous solutions produce an irregular rough and polycrystalline material, with very little chance to tune transport properties, films grown in non-aqueous solvents improve considerably homogeneity, surface roughness, and density. It is also demonstrated how the crystal texture of the films can be controlled with electroplating parameters. This allows orienting anisotropy axes directly during electroplating and thus tune electrical and thermal conductance depending on device requirements. This a significant step toward direct electrodeposition of Bi films with good transport properties, still a significant technological challenge. In order to have reasonable quantitative objectives for physical properties such as surface roughness, crystalline texture, electrical conductivity, etc. Bismuth films are also grown by Physical Vapor Deposition, characterized and compared with the electroplated.

Stabilizer-free bismuth nanoparticles for selective polyol electrooxidation

“…Figure 1A shows the optical image of the as-prepared Bi PCs-coated GCE, featuring numerous crystals at the micrometer scale (mainly 7-20 mm) anchoring on the smooth glassy carbon surface. Atomic force microscopy (AFM) image (Figure 1B) reveals the typical step formation on the surface of the crystal, a characteristic trait of Bi as a hopper crystal: quicker edge growth than facial crystallization (Cereceda-Company and Costa-Kramer, 2018). Meanwhile, the AFM (Figure 1C) and transmission electron microscopy (TEM, Figure 1D) images of the laser-treated sample confirm the successful preparation of Bi NPs, where the aggregation of the high surface energy NPs is also evident.…”

Development of mobile biosensor reader for wearable sweat glucose biosensor application

“…Blood glucose monitoring is a critical aspect of diabetes management. It involves measuring the concentration of glucose in the blood to monitor and control blood glucose levels [6]. The primary goal of blood glucose monitoring is to track and manage blood sugar levels, particularly for individuals with diabetes.…”

Electroplating Deposition of Bismuth Absorbers for X-ray Superconducting Transition Edge Sensors

“…Lien et al [ 23 ] found that the current density and stirring rate had a small effect on the crystal orientation, but pH was an important determinant of the crystal orientation at lower current densities. Costa et al [ 24 ] found that the Bi films showed an irregular rough and polycrystalline structure grown in aqueous solutions, and the homogeneity, surface roughness, and density could be improved when the films grown in non-aqueous solvents.…”

“…Compared with the Bi absorbers obtained by thermal evaporation, the electroplated Bi could minimize the low-energy tails of X-ray TES and realized films with a thickness of micrometers [ 19 , 25 ]. As described in [ 21 , 24 ], the elemental Bi is mainly dissolved in oxidizing acids to form colorless Bi 3+ cation. The Bi 3+ is easy to form Bi 2 O 3 precipitation even the pH rises very little.…”

“…The composition of the electroplating solution will affect the morphology of the Bi films. In this work, we investigated the electroplating process of Bi films using the main solution of Bi 3+ with glycerol, tartaric acid and potassium hydroxide as the additives [ 15 , 20 , 24 ]. The correlation of the electroplating current density and temperature with the morphology, grain structure, grain size, deposition rate and uniformity of the Bi films was studied.…”