Investigation of optical properties of silicon oxynitride films deposited by RF PECVD method

Abstract

In this study, the authors deposited silicon oxynitride films by Radio Frequency Plasma Enhanced Chemical Vapour Deposition (RF PECVD) method. The research explores the relationship between the deposition process parameters and the optical properties of the deposited SiO x N y films. The optical constants of SiO x N y films were measured and calculated by spectroscopic ellipsometry method. Additionally, the authors investigated the possibility of controlling the deposited film composition by the flow ratio of different gaseous precursors: ammonia (NH 3 ), diluted silane (2%SiH 4 /98%N 2 ), nitrous oxide (N 2 O) and nitrogen (N 2 ). The gas mixture introduced to the working chamber during the growth of the film has the influence on the Si-O and Si-N bonds formation and the ratio between these bonds determines the refractive index of the deposited film.

Synthesis of a Novel Polyethoxysilsesquiazane and Thermal Conversion into Ternary Silicon Oxynitride Ceramics with Enhanced Thermal Stability

“…On the other hand, nonstoichiometric silicon oxynitride (SiO x N y ) films can be fabricated by plasma enhanced chemical vapour deposition (PECVD) [12,13,14,15,16,17,18,19]. In addition to better dielectric properties, SiO x N y films show excellent optical properties.…”

“…In addition to better dielectric properties, SiO x N y films show excellent optical properties. The optical losses in SiO x N y films are significantly low, and the refractive index of the films can be controlled in the wide range from 1.45 for SiO 2 to 2.0 for Si 3 N 4 [12], which can offer potential applications, such as antireflective coatings [13] and waveguide layers [14,15,16]. Moreover, SiO x N y films exhibit sufficient thermal and chemical stabilities, and can thus be expected to be used for electronic devices [13,17] and buffer layers [18,19].…”

Analysis of optical gyroscopes with vertically stacked ring resonators

“…Parameters used in the simulation are summarized in Table 1. Silicon oxynitride and silicon dioxide were considered as a core and a cladding, respectively [27]. With the chosen materials and the core width (1 µ m), the waveguide supports a single mode.…”

A Review: Preparation, Performance, and Applications of Silicon Oxynitride Film

“…Although NH 3 reacts with SiH 4 easily, the SiN x O y film produced by NH 3 at a lower temperature has a higher hydrogen content, which causes the decreased electrical performance of SiN x O y film, so some studies used RF-PECVD, with N 2 and SiH 4 as precursor gases to prepare SiN x O y film with lower hydrogen content, and some studies used RF-PECVD, with N 2 , SiH 4 and NH 3 as the front gases [76]. For example, Kijaszek et al [77] used RF-PECVD and maintained the RF of 13.56 MHz, pressure, power, and substrate temperature (350 °C), and controlled the composition of SiN x O y film by the flow ratio of different gaseous precursors: NH 3 , 2% SiH 4 /98% N 2 and N 2 O, wherein the flow rate of 2% SiH 4 /98% N 2 and N 2 O remained the same, and the flow rate of NH 3 is adjusted to control the SiN x O y film’s performance. When the flow rate of NH 3 is low, the SiN x O y film’s hydrogen content is also lowered, and the electrical performance of the SiN x O y film is improved.…”