Properties of strontium copper oxide (SCO) deposited by PLD using the 308 nm laser and formation of SCO/Si heterostructures

Abstract

The XeCl excimer laser (308 nm) was used for depositing ptype SrCu 2 O 2 (SCO) films by pulsed-laser deposition (PLD) from undoped and Ba-doped (6%) SCO targets. The SCO films were deposited at 300 8C on glass and p-type Si substrates, while the oxygen pressure was kept constant at 5 Â 10 À2 Pa and their properties were investigated just after deposition and after annealing at 330 8C in forming gas. The films were amorphous just after deposition but became stoichiometric SrCu 2 O 2 polycrystalline after annealing and very resistive. The Ba-doped SCO films showed lower transmittance than the undoped ones but for both films the transmittance increased to around 70-80% in the NIR-IR spectrum. The optical energy gap was found to be around 3.24 eV after annealing. SCO films deposited on p-Si exhibited rectifying properties, behaving like p À -SCO/p-Si heterojunctions and their I-V and C-V characteristics were examined with temperature. An explanation of the diode behaviour is attempted based on materials properties and heterodiode characteristics.

P-type Ca doped SrCu2O2 thin film: Synthesis, optical property and photovoltaic application

“…The ternary oxide SrCu 2 O 2 has a direct band gap of 3.3 eV in combination with non-toxicity and relatively low deposition temperature [22]. There are many reports on fabrication and optoelectronic applications of Sr 1−x M x Cu 2 O 2 (M = Ca, K) films [23][24][25][26][27][28][29]. To our knowledge, SrCu 2 O 2 /Si heterojunctions have been obtained by PLD with different substrate temperatures and laser wavelengths [27,28], but Sr 0.9 Ca 0.1 Cu 2 O 2 (SCCO)/Si heterojunction and its photovoltaic performance have not been investigated.…”

Structural and Electrical Studies of Boric Acid Doped Cadmium Oxide Thin Film by JNSP Technique for Optoelectronic Applications

“…New semiconductor materials and processing techniques in bulk and thin film preparation are required as semiconductor technology advances. [1][2] The first evaporated thin films were probably the deposits which faraday obtained in 1857, when he exploded metal wires in an inert atmosphere. The possibility of depositing thin metal films in a vacuum by joule heating of platinum wires was discovered by nahrword (1887) for the purpose of measuring refractive indices of metal films.…”

Effect of thermal annealing on electrical and optical properties of Ba-doped SrCu2 O2 thin films on glass substrates

“…A suitable dopant able to improve simultaneously both properties would be essential for SCO. The first principles calculations performed on SCO by Nolan show improvements related to the calculated bandgaps and hole effective masses in Ba-doped SCO in comparison with K-and Ca-doped SCO [9,28,29]. The ionic radius of Ba 2þ is larger than the Cu þ one, which results in the strong structural distortion around the dopant sites.…”

“…Thus, Ba doping of SCO might be a useful alternative approach to obtain a high transparency and good p-type semiconducting properties compared to K and Ca doping. Based on the theoretical calculation of Nolan, Louloudakis et al have reported Ba-doped SCO deposited by PLD with an optical transparency as high as 60% and a bandgap of 3.24 eV, but they gave no information about its electrical conductivity [9].…”

“…1 Introduction Transparent conductive oxides (TCOs) [1][2][3][4][5][6][7][8][9] are fascinating materials which enter in a variety of cutting-edge applications, such as solar cells, gas sensors, organic light-emitting diodes, liquid crystal and high definition displays, electrochromic windows and architectural coatings, etc. [10,11].…”