• Development  of modelling and simulation techniques, technological processes, and characterisation

  To obtain these devices we had to develop new design and simulation tools, new processing techniques and characterization tools.

  2.1. Design tools.

  The devices were designed and simulated using analithical methods and commercial softwares. We developed special tools based on home-made programmes and software programmes Opti-BPM. Opti-FDTD and 3 Lith.
  These complex programmes can also generate the mask lay-out that can be exported and further processed in the CleWin software used for mask design.
  Examples are  given in fig.9 and 10.

 
a)                                                        b)
Fig.9. a)Simulated light propagation thrrogh a 4-level Fresnel lens (Opti-BPM). b).Simulated light propagation through awaveguide realised in a  hehagonal photonic crystal (Opti-FDTD).

Fig. 10. 4-level Fresnel lens-  Masks M1 si M2 (detail) superposed (obtained  in Opti-BPM
with a special script, than imported and processed in CleWin).

2.2. Development of new processes

New processed based on the combination optical lithography- wet or RIE etching have been developed. Also EBL for the fabrication of optical components with feature size in the range of tens-hundreds of nanometers have been used for the first time in Romania.
Also replication techniques for fabrication of low cost polymeric microprism for biosensors were experimented for the first time in Romania.
To obtain SPR-based biosensors protocols for protein imobilization in sensing layers were develpoed.

2.3. Characterization tools

The characterization have been performed wising new equipment (SEM, elipsometry, white light interferometer, optical and confocal microscops).and special set-up (e.g. for focal length measurement, dependence of the sensor response on analite concentration, lens charactristics, etc.).