The alignment between the energy levels of the constituent materials of metal-oxide-semiconductor field effect transistors (MOSFET's) and dye sensitized solar cell (DSSC's) is a key property that is critical to the functions of these devices. We have measured the energy level alignment (band offsets) for metal/oxide/semiconductor (MOS) systems with high-kappa gate oxides and metal gates, and for organic dye/oxide systems. The combination of UV photoemission spectroscopy (UPS) and inverse photoemission spectroscopy (IPS) in the same vacuum system was used to measure both the occupied and unoccupied density of states (DOS), respectively, of these materials systems. Additional soft X-ray photoemission spectroscopy (SXPS) measurements were made of both the valence bands and core levels of the high-kappa systems. The combination of the UPS, IPS and SXPS measurements were used to determine the band offsets between the high-kappa oxides and the Si substrates of thin film oxide/Si samples.2.8. Schematic diagram of grating spectrometer IPS system and UPS system. 40 2.9. 2D position sensitive photon detector. . . . . . . . . . . . . . . . . . . . 41 2.10. Energy diagram for the the electron gun and the sample in inverse pho- toemission.
|Title||:||Energy Level Alignment in Metal/oxide/semiconductor and Organic Dye/oxide Systems|
|Publisher||:||ProQuest - 2008|