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Kinetics of a.c. electroluminescence in ZnS

Кинетика злектролюминесц енции под действием переменного тока в ZnS

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Il Nuovo Cimento B (1965-1970)

Summary

In this paper, a lately proposed model is used to explain some features of the a.c. electroluminescence process in Cu-doped ZnS. The model is based on the properties of stacking-fault-type linear defects lying in basal planes of hexagonal crystals. Theoretical kinetic equations are deduced to represent the behaviour of the mean value of brightness waves. These equations are compared with the observed initial building-up of luminescence. Particular attention is given to the effect of temperature. It is found, through a comparison between experimental and theoretical results, that the decrease of the mean brightness at low temperature is due to the increasing width of the forbidden-energy gap inside the linear defective regions. All the observed facts appear self-consistent if compared with the model.

Riassunto

In questo articolo, alcune caratteristiche della elettroluminescenza a.c. nello ZnS drogato con Cu sono spiegate in base ad un modello proposto di recente. Il modello è basato sulle proprietà di difetti lineari giacenti nei piani basali dei cristalli esagonali e dovuti ad errori di impilaggio. Vengono dedotte equazioni teoriche per la cinetica, capaci di rappresentare il comportamento medio delle onde di brillanza. Queste equazioni sono messe a confronto con l’andamento iniziale delle onde di brillanza. Si trova, attraverso un paragone tra risultati sperimentali e teorici che la diminuzione di brillanza a bassa temperatura è dovuta all’accresciuta larghezza del intervallo di energia proibita all’interno della regione lineare difettosa. Tutti i fatti osservati appaiono in reciproco accordo se paragonati col modello.

Реэюме

В зтой статье испольэуется недавно предложенная модель для общяснения некоторых особенностей процесса злектролюминес ценции под действием переменного тока в ZnS с присадкой Си. Эта модель основывается на свойствах линейных дефектов, типа дефектов упаковки, лежаших в баэисных плоскостях гексо-гональных кристаллов. Выводятся теоретические кинетические уравнения, чтобы представить поведение средней величины волн яркости. Эти уравнения сравниваются с наблюденной начальной эастройкой люминесценции. Особое внимание уделяется влиянию температуры. Иэ сравнения между зкспериментальными и теоретическими реэультатами получено, что уменьщение средней яркости при ниэкой температуре обусловлено увеличением щирины эапрешенной знергетической шели внутри областей линейных дефектов. Все наблюденные факты окаэываются само-согласованными, при сравнении их с рассматриваемой моделью.

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Authors and Affiliations

  1. Istituto di Fisica dell’Università, Cagliari

    P. Brovetto, V. Maxia & C. Muntoni

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  1. P. Brovetto
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  2. V. Maxia
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  3. C. Muntoni
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Work sponsored by C.N.R. under contract N. 115.0243.69.00149.

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Brovetto, P., Maxia, V. & Muntoni, C. Kinetics of a.c. electroluminescence in ZnS. Nuovo Cimento B (1965-1970) 69, 219–240 (1970). https://doi.org/10.1007/BF02710987

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  • DOI: https://doi.org/10.1007/BF02710987

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