[PDF]    http://dx.doi.org/10.3952/lithjphys.47107

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 47, 51–57 (2007)


REVERSE-BIAS LEAKAGE IN SCHOTTKY DIODES
P. Pipinys, A. Rimeika, and V. Lapeika
Department of Physics, Vilnius Pedagogical University, Studentų 39, LT-08106 Vilnius, Lithuania
E-mail: fizdidkat@vpu.lt

Received 29 January 2007

Reverse-bias current–voltage (IR–V ) characteristics of Al-n/GaAs Schottky diodes have been studied in a temperature range from 92 to 333 K. The results are explained on the basis of phonon-assisted tunnelling model. It is shown that the temperature dependence of the reverse current IR could be caused by the temperature dependence of the electron tunnelling rate from traps in the metal–semiconductor interface to the conduction band of the semiconductor.
Temperature-dependent IR–V data obtained by Zhang et al [J. Appl. Phys. 2006; 99: 023703] and Osvald et al [Microelectron. Eng. 2005; 81: 181] for Schottky diodes fabricated on n-GaN are reinterpreted in terms of a phonon-assisted tunnelling model. The temperature and bias voltages dependences of an apparent barrier height (activation energy) observed by other researchers are also explained in the framework of this model.
Keywords: GaN, 4H-SiC, pulsed VACH measurement, high electric field effects
PACS: 65.40.-b, 71.55.Eq, 72.20.Ht, 73.50.Fq


ATGALINĖ SROVĖ ŠOTKIO DIODUOSE
P. Pipinys, A. Rimeika, V. Lapeika
Vilniaus pedagoginis universitetas, Vilnius, Lietuva

Tirta krūvio pernaša Al-n/GaAs Šotkio (Schottky) dioduose. Išmatuotos srovės tankio priklausomybės 92–333 K temperatūros srityje, esant skirtingoms pridėtos atgalinės įtampos vertėms. Kai tos vertės mažos, eksperimentiškai parodyta, kad tiriamuose Šotkio dioduose atgalinės srovės tankio temperatūrinės priklausomybės yra termoaktyvacinio pobūdžio. Tokios eigos atgalinės srovės voltamperinių charakteristikų temperatūrinės priklausomybės aiškinamos fononais paskatintų elektronų tunelinių šuolių iš sandūroje esančių lygmenų į puslaidininkio laidumo juostą modeliu. Eksperimentiniai rezultatai palyginti su teorinėmis elektronų tunelinių šuolių spartos priklausomybėmis nuo elektrinio lauko stiprio ir temperatūros. Iš palyginimų gautas lokalizuotų elektronų tankis sandūros lygmenyse (≈1011 cm–2) ir įvertinti elektrinių laukų sandūroje stipriai.
Tuo pačiu modeliu aiškinamos kitų autorių išmatuotos atgalinių srovių voltamperinių charakteristikų temperatūrinės priklausomybės Ag/n-GaAs bei n-GaN Šotkio dioduose [13, 19, 26]. Taip pat aiškinamas [7, 12, 19, 20, 22] darbuose nustatytas barjero aukščio (aktyvacijos energijos) kitimas nuo pridėtos atgalinės įtampos ir temperatūros skirtingų medžiagų Šotkio dioduose.


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