Heavily Boron-Doped Silicon Layer for the Fabrication of Nanoscale Thermoelectric Devices

Abstract

Heavily boron-doped silicon layers and boron etch-stop techniques have been widely used in the fabrication of microelectromechanical systems (MEMS). This paper provides an introduction to the fabrication process of nanoscale silicon thermoelectric devices. Low-dimensional structures such as silicon nanowire (SiNW) have been considered as a promising alternative for thermoelectric applications in order to achieve a higher thermoelectric figure of merit (ZT) than bulk silicon. Here, heavily boron-doped silicon layers and boron etch-stop processes for the fabrication of suspended SiNWs will be discussed in detail, including boron diffusion, electron beam lithography, inductively coupled plasma (ICP) etching and tetramethylammonium hydroxide (TMAH) etch-stop processes. A 7 μm long nanowire structure with a height of 280 nm and a width of 55 nm was achieved, indicating that the proposed technique is useful for nanoscale fabrication. Furthermore, a SiNW thermoelectric device has also been demonstrated, and its performance shows an obvious reduction in thermal conductivity.

Heavily doped silicon: A potential replacement of conventional plasmonic metals

“…For our design, it is assumed to be doped in the range of 10 20 to 10 21 cm -3 . Carrier concentration in this range has been practically shown by Shahzad et al [9] , Linaschke et al [10] , Mizushima et al [11] , Vina et al [12] , Ma et al [13] , Miyao et al [14] and Jellison Jr et al [15] . The highest carrier concentration of 2 × 10 22 in silicon has been reported by Nobili et al [16] .…”

Electrodeposition of Bi-Te Thin Films on Silicon Wafer and Micro-Column Arrays on Microporous Glass Template

“…With the rapid development of micro-electromechanical systems (MEMS), there are important needs for managing micro-zone temperatures and powering passive devices. Therefore, TE miniaturization via MEMS has become common [10][11][12][13][14]. However, there are still many problems that limit their performance, such as the material properties, the reduced contact resistance between the materials and metal electrodes, and the preparation and arrangement of TE arm arrays with high-aspect ratios [15,16].…”

The Fabrication of Micro/Nano Structures by Laser Machining

“…For example, photolithography, X-rays, electron beams, ion beams, particle beams, and mechanical methods. Lithography has achieved unique success in creating the ability to create 2D patterns in the range of 10 nanometers to a few microns [22][23][24][25][26][27][28][29][30][31], and is a key technology that has enabled Moore's Law to expand and revolutionize computing power [32]. Nanoimprinting or injection printing produces a pattern by mechanical deformation of the imprinted resist or by pushing droplets of variable size liquid material (ink) or powder onto the substrate [33].…”