Cadmium Telluride Thin Films Grown By Atomic Layer Epitaxy

Autor: Jarmo Skarp, Aimo Rautiainen, Arla Kytökivi, Yrjö Koskinen
Rok vydání: 1991
Předmět:
Zdroj: MRS Proceedings. 222
ISSN: 1946-4274
0272-9172
DOI: 10.1557/proc-222-269
Popis: Polycrystalline CdTe films up to 2 μm thick were grown by Atomic Layer Epitaxy (ALE) at 350–450°C. The growth was carried out in a lateral flow reactor, using the elements as source materials and 25 cm2 glass/ITO and glass/ITO/SnO2 as substrates. A growth of CdS film by ALE preceded the growth of CdTe.Profilometry, X-ray diffraction analysis and scanning electron microscopy were used to characterize the films.The relatively high vapor pressure of CdTe determined the upper limit of the processing window, while the small vapor pressure of Te2 set a practical lower limit of 390–400°C.The CdTe films were smooth up to 100–500 nm depending on the temperature and the substrate surface. Development of surface roughness was detected as the growth process proceeded. At the same time there was an increase of the effective surface area of the film, observed as a significant increase in the macroscopic growth rate. The greater surface roughness was also evident in the reduced degree of (111) orientation.The CdS/CdTe structure was investigated for its potential in solar cell applications.
Databáze: OpenAIRE
Externí odkaz: