Papers by Keyword: Diffusion Current

Abstract: This paper presents an investigation of the impact of a Highly Doped Drain (HDD) implantation after epitaxial deposition on Si1-xGex S/D junction characteristics. While the no HDD diodes exhibit the usual scaling of the leakage current density with Perimeter to Area (P/A) ratio, this is not the case for the HDD diodes, showing a smaller perimeter current density JP for smaller window size structures, corresponding with larger P/A. This points to a lower density of surface states at the Shallow Trench Isolation (STI)/silicon interface, which could result from a lower compressive stress. In order to examine the role of the HDD implantation damage, Transmission Electron Microscopy (TEM) inspections have been undertaken, which demonstrate the presence of stacking faults in small active SiGe regions. These defects give rise to local strain relaxation and, therefore, could be at the origin of the lower STI/Si interface state density. The window size effect then comes from the active area dependence of the implantation defect formation.

Abstract: This paper aims at reviewing the possibilities of using p-n junction diodes for lifetime and defect analysis in semiconductor materials. In a first part, the theoretical basis of lifetime extraction based on p-n junction current-voltage and capacitance-voltage characteristics will be discussed. In the next parts, these methods will be applied to different cases relevant for advanced semiconductor materials and device processing. First, the impact of the initial interstitial oxygen content and thermal pre-treatment of Czochralski silicon substrates on the carrier generation and recombination lifetime is discussed. A comparison will also be made with epitaxial and Float-Zone silicon. In a next part, the impact of proton-irradiation damage on the diode behavior will be presented. In the final part, the application of the technique on SiGe and Ge based p-n junctions is described. Whenever possible and useful, the information extracted from p-n junction characteristics will be compared with direct lifetime measurements using microwave techniques. Additional defect information has also been gained from other well-known techniques like Deep- Level Transient Spectroscopy (DLTS), Electron-Beam-Induced Current (EBIC), etc and will be correlated with the p-n junction results. The review is wrapped up in a summary followed by an outlook on future evolution and requirements.