Amorphous chalcogenide-based optoelectronic platform for next generation optoelectronic technologies

The study of materials which exhibit electrical or optical properties has played a major role in enabling all of modern technology and in particular electronics, computing and communications. As these technologies have been developed, existing materials have also been modified and pushed close to their limits of what is technical feasible.

Optical communication and data transfer is widely known as being much quicker as information can be moved at the speed of light. However, whenever it interacts with electronics the data transfer and processing must slow down to the speed of the microelectronic processors. There is a strong desire and a compelling argument therefore to develop an 'optoelectronic' technology which is a hybrid of the optical and electronic systems but without the current limitations imposed by the two current technologies working independently.

This proposal will address the marriage of established ion-implantation technology with the emerging potential of chalcogenide glasses as electrically-active optoelectronic materials. The electrical properties of chalcogenides are of great technological importance, for example in phase-change memory. However, these properties are comparatively insensitive to compositional variation, or impurities present during synthesis, due to auto-compensation involving dangling-bonds and charge centres.

As a result conventional glass-doping methods have proved to be insufficient to allow controlled modification of chalcogenide material's electronic properties despite their inherent semiconductor nature. The optical properties of chalcogenide materials are of equal technological interest due to their near and mid-infrared transmission and non-linear properties, to name a few. However, similarly to the electrical properties, it has generally proven difficult to modify these optical properties during preparation.

Ion-implantation is essential to modern integrated-circuit (IC) manufacture and is used for almost all doping in silicon IC's. Using the power of ion-implantation, we aim to radically expand the functionality of these emerging chalcogenide materials through post-synthesis non-equilibrium doping.  The focus of this proposal is to enable the controlled modification of their properties for the first time.