Silicon-Rich Oxide Obtained by Low-Pressure Chemical Vapor Deposition to Develop Silicon Light Sources

Abstract

Off stoichiometric silicon oxide, also known as silicon-rich oxide (SRO), is a lightemitting material that is compatible with silicon technology; therefore, it is a good candidate to be used as a light source in all-silicon optoelectronic circuits. The SRO obtained by low-pressure chemical vapor deposition (LPCVD) has shown the best luminescent properties compared to other techniques. In spite of LPCVD being a simple technique, it is not a simple task to obtain SRO with exact silicon excess in a reliable and repetitive way. In this work, the expertise obtained in our group to obtain SRO by LPCVD with precise variation is presented. Also, the characteristics of this SRO obtained in our group are revised and discussed. It is demonstrated that LPCVD is an excellent technique to obtain single layers and multilayers of nanometric single layers with good characteristics.

On the role of the atomic bond types in light emission from Si nanoparticles

“…As mentioned, it is generally accepted that the PL in SRO is caused by the combination of defect-related radiative centers, and quantum confinement phenomena. 6,8,9 In accordance to this, the experimental results were fitted to the sum of two Gaussian components. It was observed that the spectra is indeed composed by the contribution of two bands, hereafter referred to as PL 1 and PL 2 .…”

“…One of the most useful features of the SRO is the possibility of tuning the characteristics of its emission spectrum, which can comprehend nearly all the visible range, and is susceptible of modification trough the use of different fabrication techniques and conditions. 6,7 Whereas it has been reached a consensus in that the luminescence in these materials is caused by a combination of defect-related emission and quantum confinement phenomena, 6,8,9 it still exists a lack of a precise knowledge regarding how each contributes to the overall spectrum, and how this is related to the atomic characteristics of the material. Furthermore, the parameters used to define its characteristics are not common for all fabrication techniques.…”

“…For instance, if it is obtained by Chemical Vapor Deposition (CVD), it is common to define the material by the value R 0 if it was produced by Low Pressure CVD, which is related to the ratio of the precursor gases; but it must be used a particular factor which depends on the gas employed for that specific fabrication, and the way of calculating R 0 is not the same if the film was obtained by Plasma Enhanced CVD. 9 Moreover, if the SRO is fabricated using Ionic Implantation of Si in SiO 2 , the dose is usually the parameter of choice to define it, but it depends on the energy, number of implantations; and so on. Because of this lack of a common figure, the comparison of films obtained by different methods, conditions, and even facilities, is a difficult task, constituting a setback for the optimization and use of this very promising material in a larger scale.…”

Luminescence from Si-Implanted SiO2-Si3N4 Nano Bi-Layers for Electrophotonic Integrated Si Light Sources

“…The use of nano-structured Si-based materials has been demonstrated to be a viable alternative for producing fully monolithic electrophotonic systems obtained solely by complementary metal oxide semiconductor (CMOS) techniques [1,2,3]. In particular, light emitters using SixNy-SiOx nano-bilayers are promising for several applications, due to the combination of a wide visible spectrum and well-controlled photoluminescence (PL) provided by silicon-rich oxide (SRO) [2], and the possibility of improving efficiency [1], carrier injection due to lower energy barriers [4], and quantum yields [5] provided by silicon nitride and oxynitrides for electroluminescence (EL). On the other hand, planar waveguides (WG) transmitting injected or optically stimulated visible light have shown to be very promising for application in the field of integrated optical sensors and biosensors [6].…”

Progresses in Synthesis and Application of SiC Films: From CVD to ALD and from MEMS to NEMS

“…Furthermore, a LPCVD reactor allows operating more varieties of precursors and reduces the incorporation of impurities in the as-deposited films [ 28 ]. The only differences are related to the process reactor that must withstand a high-pressure gradient and the insertion of a vacuum system at the exhaust point of the reactor [ 37 ].…”