Ellipsometric study of refractive index anisotropy in porous silicon

Krzyżanowska, Halina; Kulik, M.; Żuk, J.

doi:10.1016/s0022-2313(98)00093-3

Cited by 23 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The preferred direction of porous silicon structures is perpendicular to the substrate-porous interface. All the studied samples exhibit optical anisotropy as observed in our ellipsometric measurements [21].…”

Section: Methodssupporting

confidence: 73%

Hydrogen and oxygen concentration analysis of porous silicon

Krzyżanowska¹,

Kobzev²,

Żuk³

et al. 2008

Journal of Non-Crystalline Solids

Self Cite

View full text Add to dashboard Cite

Section: Methodssupporting

confidence: 73%

Hydrogen and oxygen concentration analysis of porous silicon

Krzyżanowska¹,

Kobzev²,

Żuk³

et al. 2008

Journal of Non-Crystalline Solids

Self Cite

View full text Add to dashboard Cite

“…The quantum confinement effects must be taken into account when the pore walls thickness is approximately or less than 3 nm 14 . Finally, the microscopic column-like structure, which under certain circumstances can lead to anisotropic behavior of the optical response, must be considered too 9 15 .…”

Section: Methodsmentioning

confidence: 99%

“…Several ellipsometric optical models have been applied to a great variety of pSi structures and after a considerable amount of debate about the reliability and validity of those models, some commonly accepted results give the guidelines that set a point of departure in the analysis of specific samples. These results were obtained mainly from two approaches that have been particularly successful: the gradual porosity 7 and the morphological anisotropy models 9 . Each of them has advantages and disadvantages, however, the boundary of their applicability has not been well defined so far and results from other characterization techniques such as Scanning Electron Microscopy (SEM), could be determinant to complement the optical analysis based on these models.…”

mentioning

confidence: 99%

Role of an Oxidant Mixture as Surface Modifier of Porous Silicon Microstructures Evaluated by Spectroscopic Ellipsometry

Escobar

Nava

Río

et al. 2016

Sci Rep

View full text Add to dashboard Cite

Current research on porous silicon includes the construction of complex structures with luminescent and/or photonic properties. However, their preparation with both characteristics is still challenging. Recently, our group reported a possible method to achieve that by adding an oxidant mixture to the electrolyte used to produce porous silicon. This mixture can chemically modify their microstructure by changing the thickness and surface passivation of the pore walls. In this work, we prepared a series of samples (with and without oxidant mixture) and we evaluated the structural differences through their scanning electron micrographs and their optical properties determined by spectroscopic ellipsometry. The results showed that ellipsometry is sensitive to slight variations in the porous silicon structure, caused by changes in their preparation. The fitting process, based on models constructed from the features observed in the micrographs, allowed us to see that the mayor effect of the oxidant mixture is on samples of high porosity, where the surface oxidation strongly contributes to the skeleton thinning during the electrochemical etching. This suggests the existence of a porosity threshold for the action of the oxidant mixture. These results could have a significant impact on the design of complex porous silicon structures for different optoelectronic applications.

show abstract

“…Anisotropy of PS depends on the crystalline orientation of the silicon substrate. Birefringence has been reported in (100), (111) and (110) oriented PS [53,54,55,56,57]. In all these cases, the PS layer can be assumed to be uniaxial, and the direction of the optical axis to be normal to the surface for the (100) and (111) …”

Section: Dielectric Function and Refractive Indexmentioning

confidence: 99%

Porous Silicon

Ossicini¹,

Pavesi²,

Priolo³

2003

Springer Tracts in Modern Physics

View full text Add to dashboard Cite

In 1990 it was proposed that Si when rendered porous can be an efficient light emitting system, as efficient as many III-V semiconductor systems [1]. The reason for this was attributed to the low dimensionality of the surviving Si skeleton. In addition other effects were recognized: (1) the large photon extraction efficiency due to the decrease in the effective refractive index and (2) the confinement of the carriers in regions free of recombination centers. After this very surprising report, a huge number of papers was published trying to understand the optical properties of porous silicon (PS) and the physical mechanism at the heart of the large luminescence efficiency. Soon it was realized that PS is a very fragile and highly reactive material so that many of its properties are age dependent and unstable. Over the years, sizeable progress was made both in terms of improvement of its stability and in term of efficiency of the device. Microelectronics compatibility of PS was demonstrated and integration of driving circuits with a light emitting element was performed [2]. At the same time microcavities with improved light emission properties were demonstrated [3]. At the end of 2000 another paper shocked the silicon community: the report on light amplification or optical gain in silicon nanocrystals [4]. This paper raises big hopes of the development of a silicon laser even though it is not yet clear whether PS can be used as an active material.In this chapter we will try to review the most important results about the exploitation and the understanding of the properties of PS. The chapter is divided into six parts. The first introduces how porous silicon is made. The second is aimed to demonstrate that the structure of PS is a collection of nanometric objects that contribute to the light emission process. The relevant role of the surface chemistry is underlined. The third and fourth parts discuss the essential features of the absorption and luminescence of PS in order to discriminate between the models of the recombination mechanisms. The fifth presents recent progress in the field of electrical properties of PS. The section six is an overview of the application of PS in light emitting diodes.In the last few years various conference proceedings [5], review articles [6] and edited books [7] have been published on PS.

show abstract

Ellipsometric study of refractive index anisotropy in porous silicon

Cited by 23 publications

References 10 publications

Hydrogen and oxygen concentration analysis of porous silicon

Hydrogen and oxygen concentration analysis of porous silicon

Role of an Oxidant Mixture as Surface Modifier of Porous Silicon Microstructures Evaluated by Spectroscopic Ellipsometry

Porous Silicon

Contact Info

Product

Resources

About