Oxide Passivated Nanocrystalline Silicon Trap-Controlled memory Devices

An alternative to the single floating gate on a standard EEPROM device could be a continuous semi insulating layer in which the distribution of charge can be controlled. By partial oxidation of porous silicon, a new material named Oxide Passivated Nanocrystalline Silicon (OPNSi) is formed, which has embedded Si nanocrystals in a porous glass structure. With oxide barriers between silicon nanocrystals, carriers can be confined to the silicon crystallites or trapped at interface states on the surface of these nanocrystals. With the assistance of an electric field, carriers can undergo direct tunneling through the very thin barriers and alter the charge distribution within the OPNSi layer. The placement of charge within the layer will determine the field-effect on the underlying silicon substrate. A nondestructive read would take place at low control-gate bias, and possibly result in faster write/erase cycles compared to traditional EEPROM. Another fundamental limitation of today’s flash EEPROM is that each memory cell requires a pass-gate and a 3-terminal transistor structure, which limits the size of each cell. The OPNSi Diode will also be investigated as a possible candidate for a 2-terminal X point array memory device

An evaluation of indirect taxes in Turkey

The share of indirect taxes in tax revenues, specifically consumption taxes, is quite high in Turkey when compared to other OECD economies. This emphasis on indirect taxes in Turkey, as well as other developing economies, is argued to emerge from the inability of the government to collect direct taxes because of the existence of a large informal sector that is not easily taxable. It has been suggested that the recent increase in the indirect taxes puts the burden on mostly the poor, raising concerns of inequality. This paper evaluates the efficiency of the current indirect taxes in Turkey by taking into account distributional concerns. Using data from the 2003 Household Budget Survey, we estimate elasticities of different consumption goods and services using AIDS method. We then perform a marginal tax reform analysis to assess the efficiency of indirect taxes. Our findings indicate that there is room for improvement and the current tax rates are not optimal.Indirect taxes; Household survey; Marginal tax reform; AIDS estimation

Conference of Microelectronic Research 1999

https://scholarworks.rit.edu/meec_archive/1008/thumbnail.jp