Thermoelectric, magnetotransport, and ultrafast dynamics of bismuth telluride thin films grown using pulsed laser deposition: effects of substrate temperature and post-annealing
Le Thi Cam Tuyen, Bih-Show Lou, Jyh-Wei Lee, Ngo Ngoc Uyen, Phuoc Huu Le, Chien-Neng Liao, Chih-Wei Luo, Jiunn-Yuan Lin
TL;DR
Researchers optimized bismuth telluride thin films for thermoelectric performance by adjusting deposition and annealing temperatures, achieving a top power factor and revealing topological properties.
Contribution
Systematic optimization of PLD-grown Bi2Te3 thin films via substrate and annealing temperature control, achieving a 19% improvement in thermoelectric power factor.
Findings
Near-stoichiometric Bi2Te3 films deposited at 250–300°C showed reduced carrier concentration and enhanced mobility.
Post-annealing at 250°C improved the power factor to 23.8 µW·cm−1·K−2, a 19% increase over as-deposited films.
Low-temperature transport measurements revealed two-dimensional weak antilocalization behavior, indicating topological surface states.
Abstract
n-Type Bi2Te3 and Bi4Te5 thin films were grown on SiO2/Si substrates via pulsed laser deposition (PLD) at substrate temperatures (TS) ranging from 25°C to 350°C under 220 mTorr He. Film morphology evolved from nanoparticles to layered hexagonal platelets with increasing TS, accompanied by a shift in preferred orientation from (015) to highly (00 l)-oriented textures. Composition varied from Te-rich at low TS to Te-deficient at 350°C. Near-stoichiometric and (00 l)-textured Bi2Te3 thin films deposited at 250–300°C exhibited reduced carrier concentration (~9.5 × 1019 cm−3), significantly enhanced mobility (up to 81.2 cm2/V·s), and a maximum thermoelectric (TE) power factor (PF) of 20.0 µW·cm−1·K−2. To further enhance the TE performance, Bi2Te3 films grown at 200, 250, and 300°C were in-situ annealed in helium gas at 220 mTorr for 60 min at annealing temperatures (TA) of 200, 250, 300, and…
Genes, proteins, chemicals, diseases, species, mutations and cell lines named across the full text — each resolved to its canonical identifier and authoritative record.
Click any figure to enlarge with its caption.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14
Figure 15
Figure 16
Figure 17
Figure 18
Figure 19
Figure 20
Figure 21
Figure 22
Figure 23
Figure 24
Figure 25
Figure 26
Figure 27
Figure 28
Figure 29
Figure 30
Figure 31
Figure 32
Figure 33
Figure 34
Figure 35
Figure 36
Figure 37
Figure 38
Figure 39Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsAdvanced Thermoelectric Materials and Devices · Chalcogenide Semiconductor Thin Films · Advanced Semiconductor Detectors and Materials