Epitaxial Growth of Bi2Se3 Infrared Transparent Conductive Film and Heterojunction Diode by Molecular Beam Epitaxy

Abstract

Epitaxial n-type infrared transparent conductive Bi2Se3 thin film was cultivated by molecular beam epitaxy (MBE) method on Al2O3 (001) substrate. The orientation between Bi2Se3 and the substrate is Bi2Se3(001)//Al2O3(1 2¯ 10). Conducting mechanism ensued the small-polaron hopping mechanism, with an activation energy of 34 meV. The film demonstrates conductivity of n-type, and the resistivity is 7 × 10−4 Ωcm at room temperature. The Film exhibits an excellent carrier mobility of 1,015 cm2/Vs at room temperature and retains optical transparency in the near-infrared (>70%) and far-infrared (>85%) ranges. To the best of our knowledge, the Bi2Se3 film yields the best result in the realm of n-type Infrared transparent conductive thin films generated through either physical or chemical methods. To demonstrate the application of such films, we produced N-Bi2Se3/P-CuScO2 heterojunction diode device, the ∼3.3 V threshold voltage of which conformed fairly well with the CuScO2 bandgap value. The high optical transparency and conductivity of Bi2Se3 film make it very promising for optoelectronic applications, where a wide wavelength range from near-infrared to far-infrared is required.

Enhanced Photoresponse of High Crystalline Bi2Se3 Thin-Films Using Patterned Substrates

“…Thus, when compared to Bi 2 Se 3 /Al 2 O 3 , Bi 2 Se 3 /PSS has 65 times lower carrier concentration and 21 times higher Hall mobility. Here, a very large difference in the partial pressure between Bi and Se metals causes Se vacancies in the Bi 2 Se 3 thin film, which role as donors to give a rather high carrier concentration and low carrier mobility. , As aforementioned, by additionally supplying Se ions during the growth and covering high-purity Bi 2 Se 3 powder with a Bi metal, we achieved higher mobility and lower concentration of Bi 2 Se 3 /PSS than the previous report …”

“…31,49 As aforementioned, by additionally supplying Se ions during the growth and covering high-purity Bi 2 Se 3 powder with a Bi metal, we achieved higher mobility and lower concentration of Bi 2 Se 3 /PSS than the previous report. 50 Photoresponse of the Device Fabricated with the Bi 2 Se 3 Thin Films. The potential use of Bi 2 Se 3 /PSS thin films was accomplished by fabricating them as a photoconductive detector as schematically shown in Figure 5a.…”

van der Waals Epitaxy of Bi Nanowires and Bi2Se3 Thin Films on an Antiferromagnetic Substrate of CoNb3S6

“…These compact islands have an average height of 22 Å, identical to 2 QL Bi 2 Se 3 . 30,31 These behaviors indicate a 2D growth mode for Bi 2 Se 3 on CoNb 3 S 6 . The different growth modes of Bi and Bi 2 Se 3 on CoNb 3 S 6 might be originated from the lower surface energy of Bi 2 Se 3 (0.0214 J/m 2 ) 32 than that of Bi (0.43 J/m 2 ).…”

“…Figure b depicts the Bi 4f core level spectrum. The two prominent peaks at 157.4 and 162.7 eV are assigned to the Bi 4f 7/2 and Bi 4f 5/2 doublets of Bi 2 Se 3 , respectively, akin to that on Si and Al 2 O 3 (001) Figure c demonstrates the Se 3d core levels spectrum.…”

“…The two prominent peaks at 157.4 and 162.7 eV are assigned to the Bi 4f 7/2 and Bi 4f 5/2 doublets of Bi 2 Se 3 , respectively, akin to that on Si 35 and Al 2 O 3 (001). 31 Figure 5c demonstrates the Se 3d core levels spectrum. The two peaks located at 53 and 53.6 eV are attributed to the Se 3d 5/2 and Se 3d 3/2 doublets, in line with previous results of the 3d orbitals of Se in Bi 2 Se 3 .…”