Silicon photonics: the early years

Abstract

The purpose of this paper is to set the scene for what promises to be an outstanding conference. To this end the paper will survey the early work in silicon photonics from the late 1980s to the mid 1990s. This was when the more fundamental studies of basic building blocks were carried out, such as study of the silicon optical waveguide itself, the contributions to loss and improvement of waveguiding devices. Issues such as how to achieve modulation, and how to implement a modulator, the criteria for single mode propagation will also be covered, as well as work on the beginnings of optical circuits in silicon and SOI. The focus will be upon pure silicon, usually, but not exclusively in the form of Silicon on Insulator (SOI), as opposed to work on compounds such as SiGe or SiC. Much of this work still resonates with work being carried out today, because the move to smaller and more efficient devices means that some of these issues must be revisited in order to achieve optimal device performance. Hence the paper will provide a summary of the early work on silicon photonics, and attempt to relate it to some of the issues being studied today.

The Emergence of Silicon Photonics as a Flexible Technology Platform

“…In the late 1980s and early 1990s, Separation by IMplantated OXygen (SIMOX) and Bond and the Etchback SOI (BESOI) techniques were the two main methods for SOI wafer fabrication [22], [33]- [39]. Initially, very large propagation losses (∼30 dB/cm) from a 2-μm-thick planar waveguide [37] were demonstrated in these wafers.…”

“…Around 1989, Kurdi et al [31] and Davis et al [33] reduced propagation losses to acceptable levels achieving 4 and 1 dB/cm, respectively. Multiplelayer waveguiding structures using SIMOX fabrication technology were also demonstrated [22], [32], [35]. During the1990s, most of the attention was turned to rib waveguides, structures that could confine light in both dimensions.…”

Introductory Chapter: Unique Applications of Silicon Photonics

“…Silicon photonics is accepted as the next-generation com-photonics-high data densities and transmission over longer distances. One potential application was of waveguides in silicon-on-insulator (SOI) wafer structures in 1985 [5,6], which was commercialized later in 1989 by Bookham Technology Ltd. [7].…”

Integration of Electronics and Planar Waveguide Photonics in the Silicon-on-Insulator Platform

“…Rickman et al confirmed that the propagation loss was not going to be a serious issue in the development of the SOI technology [30]. The earliest SOI planar waveguides were rib waveguides with multi-micron width [31].…”