Large grain electroluminescent ZnS:Mn thin films grown by quasi-rheotaxy on insulating materials

In a previous paper we proved the possibility of growing thin ZnS:Mn films of good morphological quality on metal substrates with the aid of the quasi-rheotaxy technique. In the present paper, besides confirming the previous results, we demonstrate that the growth of ZnS:Mn by means of the quasi-rheotaxy technique is also possible on insulating materials. In particular we show that the insertion of the ZnS:Mn film between two very thin layers of As2S3, Sb2S3 and B2O3 in a metal-insulator-semiconductor-insulator-metal device, allows the growth of the active layer with superior morphological characteristics if compared with the already rather satisfactory results previously obtained on metal substrates. Finally we discuss the luminance-voltage characteristics of one of our electroluminescent devices, which shows good symmetrical brightness with respect to the positive and negative pulses of the a.c. excitation voltage. (C) 2001 Elsevier Science B.V. All rights reserved.