Teaching integrated circuit and semiconductor device design in New Zealand: the University of Canterbury approach

Teaching the practical aspects of device and chip design in New Zealand presents many problems, including high manufacturing costs, long lead times, and the lack of local industry strength. Nonetheless, it is possible to overcome these issues. This paper describes the courses in these areas at the University of Canterbury, including a practical IC design project that has been running successfully for the past four years. The IC design project takes final year students through a full custom design using modern design tools and fabrication processes. The design is quite straightforward — a 4-bit arithmetic logic unit — but it emphasises the importance of design, simulation and testing. The final circuits contain a few hundred transistors, so good practice is essential. Twelve designs are integrated on to a single chip to keep costs down, and individual designs are addressed via multiplexers. The designs are fabricated using a 0.5 micron process, accessed through a multi-project vendor (MOSIS). Getting chips back from a manufacturer is significantly more motivating for the students than just performing a paper design

Melody recognition with learned edit distances

In a music recognition task, the classification of a new melody is often achieved by looking for the closest piece in a set of already known prototypes. The definition of a relevant similarity measure becomes then a crucial point. So far, the edit distance approach with a-priori fixed operation costs has been one of the most used to accomplish the task. In this paper, the application of a probabilistic learning model to both string and tree edit distances is proposed and is compared to a genetic algorithm cost fitting approach. The results show that both learning models outperform fixed-costs systems, and that the probabilistic approach is able to describe consistently the underlying melodic similarity model.This work was funded by the French ANR Marmota project, the Spanish PROSEMUS project (TIN2006-14932-C02), the research programme Consolider Ingenio 2010 (MIPRCV, CSD2007-00018), and the Pascal Network of Excellence

HIGHLY NONLINEAR OPTICAL EFFECTS IN LIQUID CRYSTALS

Le champ optique d'un laser continu est assez fort pour induire un grand changement de l'indice de réfraction d'un cristal liquide. La transition structurelle induite par un champ optique peut avoir lieu. La grande nonlinearité optique peut mener à des phénomènes d'optique nonlinéaire intéressants.CW laser fields are strong enough to induce a large refractive index change in a liquid crystal. Optical-field-induced structural transition can occur. The large optical nonlinearity can lead to some unusual highly nonlinear optical phenomena

Multilevel silicon diffractive optics for terahertz waves

A multilevel microfabrication process has been developed to produce silicon Fresnel lenses for terahertz waves. A repeated binary fabrication process was used to create lenses with up to eight levels in complexity and these lenses have been compared to both less complex structures and refractive optic lenses. The microfabrication required deep reactive ion etching and multilevel resist processing using SU8 photoresist. At the design frequency of 1 THz an eight-level lens showed significant improvement in intensity at the focus and had much reduced energy lost into sidelobes compared with refractive lenses