Attenuated total reflection spectroscopy for infrared analysis of thin layers on a semiconductor substrate

Abstract

A theoretical analysis based on a perturbation method is used to elucidate the results of attenuated total reflection (ATR) measurements performed on silicon oxide layers of different thicknesses on silicon substrates. This analysis shows that the absorbance ATR spectrum in p polarization is the image of the layer energy loss function, under specific conditions. It is pointed out that the enhanced sensitivity of ATR is controlled by the air gap thickness, the optical properties of the media involved, and the probing light polarization. An exact ATR spectrum simulation using a matrix formalism showed that straightforward interpretation in terms of the layer dielectric function is limited to a very narrow layer thickness range. The ATR spectrum fitting process is considered for layers out of this range and evaluated for the interpretation of experimental silicon oxide layer spectra.

Growth by Liquid‐Injection MOCVD and Properties of HfO2 Films for Microelectronic Applications

“…XRR was performed on thin films using the same radiation. Infrared spectroscopy in the ATR configuration was carried out using an experimental, home-made setup described, in detail, elsewhere [34]. The sample was pressed between a germanium prism and a tip mounted on a micrometric screw.…”

Study of interfacial reactions and phase stabilization of mixed Sc, Dy, Hf high-k oxides by attenuated total reflectance infrared spectroscopy

“…Band assignments and interpretations are as follows. At 1240 and 1065 cm À1 the longitudinal (LO) and transverse optic (TO) band of SiO 2 are found [15]. At 1100 cm À1 Hf-O-Si vibrations would be expected [19], but comparison with the blank substrates shows that any intensity in this area is due to the SiO 2 from the substrate [20].…”

“…Normal transmission measurements are insufficiently sensitive, but the surface sensitivity can be greatly enhanced in attenuated total reflectance (ATR) [14]. The sensitivity enhancement depends on the angle of incidence, the thickness of the air gap and the dielectric constants of the ATR crystal and the film's substrate [15,16]. Here, we apply grazing angle attenuated total reflectance Fourier transform infrared (GATR-FTIR) to several high-k films of recent interest, Hf, Dy and Sc oxides, which were deposited by atomic vapour deposition (AVD) or atomic layer deposition (ALD) for high quality film growth with atomic precision.…”

Toward Successful Integration of Porous Low-k Materials: Strategies Addressing Plasma Damage

“…51 For thin film analysis, FTIR sensitivity can be improved by working in attenuated total reflectance (ATR) or multiple internal reflection (MIR) mode. 52,53 X-ray reflectivity.-X-Ray reflectivity (XRR) is a method that involves exposing a sample to a monochromatic X-ray beam, at grazing incident angles (typically 0…”