Third party funded individual grant
Acronym: FR 713/14-1
Start date : 02.10.2017
End date : 30.09.2019
To meet the contemporary developments in the information, communication, and data processing technologies, further improvements in the performance of highly integrated electron devices are indispensable. This can be achieved only by modifications of their architecture towards a three-dimensional structure together with a minimization of their dimensions on the nanometre scale. For their operation, electron devices require regions highly doped with dopant atoms (e.g. boron, phosphorus, or arsenic). In contemporary technologies, such regions are fabricated by ion implantation. In this doping process, the doping atoms are accelerated in an electric field and shot into the semiconductor. Besides the many advantages of the technique, ion implantation leads to a damage of the crystalline semiconductor materials which are in part hard to anneal for structures on the nanometre scale. In addition, it is increasingly difficult to dope three-dimensional structures. In consequence, as an alternative doping process, we will investigate in this project the diffusion of dopants from highly doped oxide layers. Such layers are deposited by atomic layer deposition with layer thicknesses in the nanometre range. The objective of the project is to develop and improve the respective deposition processes as well as to characterize and model the subsequent diffusion processes.
Atomic layer deposition processes for phosphorus-containing layers will be developed and investigated. Recently developed ALD processes for boron oxide and antimony oxide will be further improved and analyzed as well. These layers will be used as a dopant sources for silicon doping to produce ultra-shallow and homogeneous doped pn junctions, especially for applications, where doping on three-dimensional surface configurations is required.
In addition, suitable methods for stabilization of unstable dopant layers need to be found and analyzed. The deposited layers will be characterized and the diffusion processes in the silicon and in the oxide phase will be studied, and thus the doping processes will be modeled.