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Contains fulltext : 221738.pdf (postprint version ) (Open Access)

Contains fulltext : 221738.pdf (postprint version ) (Open Access)

Contains fulltext : 221738.pdf (postprint version ) (Open Access)

Contains fulltext : 203335.pdf (publisher's version ) (Closed access)

Contains fulltext : 203335.pdf (publisher's version ) (Closed access)

We analyze the small- and large-signal response of a photonic crystal Fano laser (PhC-FL). Conventional current modulation, as well as modulation of the laser via the mirror, is investigated using a numerical approach as well as linear smallsignal analysis. The results show that the amplitude modulation bandwidth of one of the laser ports (the through-port) and the frequency modulation (FM) bandwidth of another port (the cross-port) extend to the THz region. Large-signal simulations of the laser response to a 500 Gbit/s pseudo-random bit sequence modulation of the nanocavity are in good agreement with the predictions of the small-signal analysis. Finally, it is investigated how the design of the Fano mirror, in particular, the qualityfactor (Q) of the nanocavity, affects the modulation properties.

In this thesis selected applications of both minority and majority carrier conductor- thin insulator - semiconductor (CIS) tunnel structures to microelectronic devices such asbipolar and field-effect transistors are studied. Minority carrier CIS structures have propertieswhich approach those of an ideal p-n junction diode when the insulator issufficiently thin to allow a large current to flow through it. The effective junction depth ofsuch a CIS diode is of the order of the thickness of the electrostatically induced inversionlayer at the semiconductor-insulator interface. On the other hand, majority carrier CIStunnel diodes have shown interesting properties such as an internal current gain.First, by replacing the normally diffused emitters of silicon bipolar transistors withmetallic conductor CIS heterojunction tunneling emitters, significant improvements in thecurrent gain and in the breakdown voltage of super gain silicon bipolar transistors havebeen obtained. Current gains above 3xl04 have been achieved for devices with a breakdownvoltage in excess of 30V. Lateral bipolar transistors having such CIS emitters andcollectors have been fabricated. These are shown to possess lower leakage and highercurrent gains than those previously reported.Then, the emitter of a newly proposed transistor structure, the bipolar inversionchannelfield-effect transistor (BICFET), is replaced by a majority carrier CIS tunnelemitter. Experimental BICFETs of this type are fabricated more simply than originallyproposed and are shown to possess characteristics of the general form predicted. Both Aland n + poly have been used as the conductor overlying the tunnel insulator. In the lattercase, where a self-aligned scheme is implemented, a good quality interfacial oxide isshown to have an essential role in device operation.The shallow junction depth of the minority carrier CIS structures has been used toadvantage by replacing the normally diffused source and drain regions of a MOSFET withsuch