Patent application number | Description | Published |
20090050955 | NONVOLATILE SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME - A charge storage layer interposed between a memory gate electrode and a semiconductor substrate is formed shorter than a gate length of the memory gate electrode or a length of insulating films so as to make the overlapping amount of the charge storage layer and a source region to be less than 40 nm. Therefore, in the write state, since the movement in the transverse direction of the electrons and the holes locally existing in the charge storage layer decreases, the variation of the threshold voltage when holding a high temperature can be reduced. In addition, the effective channel length is made to be 30 nm or less so as to reduce an apparent amount of holes so that coupling of the electrons with the holes in the charge storage layer decreases; therefore, the variation of the threshold voltage when holding at room temperature can be reduced. | 02-26-2009 |
20090050956 | SEMICONDUCTOR MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - In a memory cell including an nMIS for memory formed on the sides of an nMIS for select and an nMIS for select via dielectric films and a charge storage layer, the thickness of a gate dielectric under the gate longitudinal direction end of a select gate electrode is formed thicker than that of the gate dielectric under the gate longitudinal direction center and the thickness of the lower layer dielectric film that is positioned between the select gate electrode and the charge storage layer and is nearest to a semiconductor substrate is formed 1.5 times or below of the thickness of the lower layer dielectric film positioned between the semiconductor substrate and the charge storage layer. | 02-26-2009 |
20090052259 | NON-VOLATILE SEMICONDUCTOR MEMORY DEVICE - A non-volatile semiconductor memory device is provided. A gate electrode configuring a memory cell is turned into floating state and a potential of a gate electrode adjacent thereto is changed, and reduce the potential of the gate electrode by this change of potential and the capacitive coupling. Furthermore, charge sharing is carried out by connecting two gate electrodes, and the voltage of the gate electrode is reduced by capacitive coupling with another gate electrode adjacent thereto, to largely reduce the potential of the gate electrode. Thereby, the voltage level generated by the charge pump circuit can be reduced. As a result, the size of the charge pump circuit can be reduced, or the circuit itself can be eliminated, resulting in reduction of the chip area. | 02-26-2009 |
20090134449 | NON-VOLATILE SEMICONDUCTOR MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - Provided is a nonvolatile semiconductor memory device highly integrated and highly reliable. A plurality of memory cells are formed in a plurality of active regions sectioned by a plurality of isolations (silicon oxide films) extending in the Y direction and deeper than a well (p type semiconductor region). In each memory cell, a contact is provided in the well (p type semiconductor region) so as to penetrate through a source diffusion layer (n | 05-28-2009 |
20090273014 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - Each of a memory gate, a control gate, a source diffusion layer, and a drain diffusion layer is connected to a control circuit for controlling potential, and the control circuit operates so as to supply a first potential to the memory gate, a second potential to the control gate, a third potential to the drain diffusion layer, and a fourth potential to the source diffusion layer. Here, after setting the memory gate to be in a floating state by shifting a switch transistor from an ON state to an OFF state, the control circuit operates so as to supply a sixth potential which is higher than the second potential to the control gate to make the memory gate have a fifth potential which is higher than the first potential, thereby boosting the memory gate. | 11-05-2009 |
20100193856 | SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME - A step is provided between a substrate surface of a select gate and a substrate surface of a memory gate. When the substrate surface of the select gate is lower than the substrate surface of the memory gate, electrons in a channel upon writing obliquely flow in the step portion. Even if the electrons obtain the energy required for passing a barrier during the oblique flow, the electron injection does not occur because electrons are away from the substrate surface. The injection can occur only on a drain region side from a position where the electrons reach the substrate surface. As a result, the injection of the electrons into a gap region is suppressed, so that the electron distribution comes close to the hole distribution. Therefore, variation in a threshold value upon information retention is suppressed, and information-retaining characteristics of a memory cell are improved. | 08-05-2010 |
20100261327 | NON-VOLATILE SEMICONDUCTOR MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - Provided is a nonvolatile semiconductor memory device highly integrated and highly reliable. A plurality of memory cells are formed in a plurality of active regions sectioned by a plurality of isolations (silicon oxide films) extending in the Y direction and deeper than a well (p type semiconductor region). In each memory cell, a contact is provided in the well (p type semiconductor region) so as to penetrate through a source diffusion layer (n | 10-14-2010 |
20110235419 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - In a split gate MONOS memory which carries out rewrite by hot carrier injection, retention characteristics are improved. A select gate electrode of a memory cell is connected to a select gate line, and a memory gate electrode is connected to a memory gate line. A drain region is connected to a bit line, and a source region is connected to a source line. Furthermore, a well line is connected to a p type well region in which the memory cell is formed. When write to the memory cell is to be carried out, write by a source side injection method is carried out while applying a negative voltage to the p type well region via the well line. | 09-29-2011 |
20110242888 | SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - The semiconductor device includes the nonvolatile memory cell in the main surface of a semiconductor substrate. The nonvolatile memory cell has a first insulating film over the semiconductor substrate, a conductive film, a second insulating film, the charge storage film capable of storing therein charges, a third insulating film over the charge storage film, a first gate electrode, a fourth insulating film in contact with the set of stacked films from the first insulating film to the foregoing first gate electrode, a fifth insulating film juxtaposed with the first insulating film over the foregoing semiconductor substrate, a second gate electrode formed over the fifth insulating film to be adjacent to the foregoing first gate electrode over the side surface of the fourth insulating film, and source/drain regions with the first and second gate electrodes interposed therebetween. The conductive film and the charge storage film are formed to two-dimensionally overlap. | 10-06-2011 |
20130140622 | NONVOLATILE SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME - A charge storage layer interposed between a memory gate electrode and a semiconductor substrate is formed shorter than a gate length of the memory gate electrode or a length of insulating films so as to make the overlapping amount of the charge storage layer and a source region to be less than 40 nm. Therefore, in the write state, since the movement in the transverse direction of the electrons and the holes locally existing in the charge storage layer decreases, the variation of the threshold voltage when holding a high temperature can be reduced. In addition, the effective channel length is made to be 30 nm or less so as to reduce an apparent amount of holes so that coupling of the electrons with the holes in the charge storage layer decreases; therefore, the variation of the threshold voltage when holding at room temperature can be reduced. | 06-06-2013 |
20140092688 | Non-Volatile Semiconductor Storage Device - In a split gate MONOS memory which carries out rewrite by hot carrier injection, retention characteristics are improved. A select gate electrode of a memory cell is connected to a select gate line, and a memory gate electrode is connected to a memory gate line. A drain region is connected to a bit line, and a source region is connected to a source line. Furthermore, a well line is connected to a p type well region in which the memory cell is formed. When write to the memory cell is to be carried out, write by a source side injection method is carried out while applying a negative voltage to the p type well region via the well line. | 04-03-2014 |
20140322874 | NONVOLATILE SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME - A charge storage layer interposed between a memory gate electrode and a semiconductor substrate is formed shorter than a gate length of the memory gate electrode or a length of insulating films so as to make the overlapping amount of the charge storage layer and a source region to be less than 40 nm. Therefore, in the write state, since the movement in the transverse direction of the electrons and the holes locally existing in the charge storage layer decreases, the variation of the threshold voltage when holding a high temperature can be reduced. In addition, the effective channel length is made to be 30 nm or less so as to reduce an apparent amount of holes so that coupling of the electrons with the holes in the charge storage layer decreases; therefore, the variation of the threshold voltage when holding at room temperature can be reduced. | 10-30-2014 |