Characterization of thin films deposited by RF magnetron sputtering for use in a.c. TFEL devices

Abstract

Thin films of BaTiO 3 have been deposited by RF magnetron sputtering onto 100 mm diameter n-type single-crystal Si wafers. Full deposition and post-deposition variables have been investigated with respect to their effect on the dielectric constant and refractive index of the thin films. Specifically for use as insulators for thin film electroluminescent (TFEL) devices, the films need to exhibit a high dielectric constant and a low refractive index. The optimum fabrication route was determined to be deposition at 200 • C in a 30% O 2 in Ar atmosphere at 7 mTorr with a post-deposition anneal at 700 • C for 1 h. Demonstrated here is that films exhibiting suitable characteristics, namely, ε r = 26 and n = 2.1, for use in TFEL devices can be fabricated using RF magnetron sputter deposition.

Determination of thin film refractive index and thickness by means of film phase thickness

“…Amorphous barium titanate films are often used as insulating layers in thin film electroluminescent devices and flat panel displays in the visible spectral region [17]. High dielectric constant, low dielectric and optical losses are among the most important requirements for such insulating layers [17,18].…”

“…High dielectric constant, low dielectric and optical losses are among the most important requirements for such insulating layers [17,18]. Radio frequency (RF) sputtering deposition is a common method to deposit insulating barium titanate thin films with appropriate optical properties [18?…”

Properties of barium titanate (BaTiO3) thin films grown on silicon by rf magnetron sputtering

“…The latter result is equivalent to a large amount of trapped charge within the polycrystalline film. In the present work we report on the bulk and interface properties of BaTi03 films grown on p-silicon under the conditions for optimum growth (Craven et al 1998). …”

“…Among the various deposition techniques used so far, we can list here radio frequency (rf) diode and triode sputtering (Pratt andFirestone 1971, Panitz andHu 1979), laser ablation (Yeh et al 1993) and rf magnetron sputtering which has been demonstrated to be the most promising because it offers good reproducibility, uniformity and simplicity (Craven et al 1998). Different growth temperatures in the range from 100 up to 700°C in conjunction with a wide range of post growth annealing as well as different Ar/02 ambient have been extensively studied previously.…”