Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

TELLURIUM/GaAs HETEROJUNCTIONS FABRICATED BY THERMAL EVAPORATION IN VACUUM
Vaidas Pačebutas^a, Ričardas Norkus^b, Andrejus Geižutis^a, Viktorija Strazdienė^a, and Arūnas Krotkus^a
^aCenter for Physical Sciences and Technology, Saulėtekio 3, 10257 Vilnius, Lithuania
^bVilnius University, Saulėtekio 9, 10222 Vilnius, Lithuania
Email: vaidas.pacebutas@ftmc.lt

Received 24 October 2024; accepted 24 October 2024

Heterostructures containing thin tellurium layers thermally evaporated on differently doped GaAs substrates were systematically investigated by using THz pulse excitation spectroscopy. The observed differences of the THz excitation spectra were explained by the details of the energy band lineups in the heterostructures. Comparison of the simulation results of the heterojunction between tellurium and semi-insulating GaAs with the measured THz pulse emission spectrum allowed one to estimate the electron affinity in the tellurium layer. In addition, a near-infrared photodetector based on the Te heterojunction with n-type GaAs was demonstrated.
Keywords: tellurium/GaAs heterojunction, THz emission spectroscopy, tellurium affinity

TELŪRO/GaAs HETEROSANDŪROS, PAGAMINTOS TERMIŠKAI GARINANT VAKUUME
Vaidas Pačebutas^a, Ričardas Norkus^b, Andrejus Geižutis^a, Viktorija Strazdienė^a, Arūnas Krotkus^a

^aFizinių ir technologijos mokslų centras, Vilnius, Lietuva
^bVilniaus universitetas, Vilnius, Lietuva

Heterosandūros, pagamintos termiškai garinant plonus telūro sluoksnius ant įvairiai legiruotų GaAs padėklų, buvo sistemingai tiriamos pasitelkiant THz spinduliuotės impulsų žadinimo spektroskopiją. Stebimi THz žadinimo spektrų skirtumai buvo paaiškinti nevienodu elektronų energijos juostų išsidėstymu šiose heterosandūrose. Telūro ir pusiau izoliuojančio GaAs heterosandūrų modeliavimo rezultatų palyginimas su išmatuotu THz impulsų emisijos spektru leido įvertinti elektronų giminingumą telūre. Be to, naudojant darbe tirtą Te heterosandūrą su n-GaAs, pavyko detektuoti artimojo infraraudonojo diapazono spinduliuotę.

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