摘要:
The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lower erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole.
摘要:
The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lower erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole. However, when only some memory cells of a group have a higher erase speed, an excessive erase requiring electric charge supply occurs only in some memories and accordingly, it is possible to rapidly complete the data erase in the memory cells of the group.
摘要:
The present invention enables to complete a data erase of memory cells of a group in a semiconductor storage device where a data erase is uniformly performed to memory cells of a group until all the cell threshold values become below a reference and memory cells having a cell threshold value below a lower limit are supplied with an electric charge. When a production error occurs in such a way that some memory cells in a predetermined position of a group have a lover erase speed, the semiconductor device is formed in such a way that these memory cells have an erase speed higher than an ideal value. When some memory cells of a group have a lower erase speed, an excessive erase is performed in most memory cells of the group requiring electric charge supply, which increase the erase time as a whole. However, when only some memory cells of a group have a higher erase speed, an excessive erase requiring electric charge supply occurs only in some memories and accordingly, it is possible to rapidly complete the data.
摘要:
A first semiconductor device is formed over a substrate and includes a first insulation film, a first electrode, and a first diffusion layer. A second semiconductor device is formed over a substrate and includes a second insulation film, a second electrode, and a second diffusion layer. The second electrode is coupled to the first electrode. A control transistor allows one of a source and a drain to be coupled to the first electrode and the second electrode, allows the other one of the source and the drain to be coupled to a bit line, and allows a gate electrode to be coupled to a word line. A first potential control line is coupled to the first diffusion layer and controls a potential of the first diffusion layer. A second potential control line is coupled to the second diffusion layer and controls a potential of the second diffusion layer.
摘要:
The present invention prevents a charge-up during a wiring layer etching in a nonvolatile semiconductor storage apparatus having a floating gate and a control gate to which both of positive and negative voltages are applied during a memory cell operation. On a semiconductor substrate 51 of a first conductive type, a first well 52 of a second conductive type is formed to oppose to the first conductive type. In the first well 52, a second well 53 of the first conductive type is formed. On a main surface of the second well 53 is formed a composite gate 8 consisting of a first gate insulation film 4, a floating gate 5, a second gate insulation film 6, and a control gate 7 which are successively layered. On a surface of the second well 53 are formed by way of ion implantation, a source, a drain, and a charge-up preventing element diffusion layer 18 of the second conductive type.
摘要:
In a method for manufacturing a semiconductor memory device including a plurality of field areas, a plurality of electrode areas, a plurality of source areas and drain areas sunrounded by the field areas and the electrode areas, before forming field insulating layers for isolating the source and drain regions, impurities are introduced into the field areas between the source regions, to create an additional source region below the field insulating layer for isolating the source regions. The additional source regions are linked between the source regions.
摘要:
A first semiconductor device is formed over a substrate and includes a first insulation film, a first electrode, and a first diffusion layer. A second semiconductor device is formed over a substrate and includes a second insulation film, a second electrode, and a second diffusion layer. The second electrode is coupled to the first electrode. A control transistor allows one of a source and a drain to be coupled to the first electrode and the second electrode, allows the other one of the source and the drain to be coupled to a bit line, and allows a gate electrode to be coupled to a word line. A first potential control line is coupled to the first diffusion layer and controls a potential of the first diffusion layer. A second potential control line is coupled to the second diffusion layer and controls a potential of the second diffusion layer.
摘要:
An antifuse whose internal written information cannot be analyzed even by utilizing methods to determine whether there is a charge-up in the electrodes. The antifuse includes a gate insulation film, a gate electrode, and a first diffusion layer. A second diffusion layer is isolated from the first diffusion layer by way of a device isolator film, and is the same conduction type as the first diffusion layer. The gate wiring is formed as one integrated piece with the gate electrode, and extends over the device isolator film. A common contact couples the gate wiring to the second diffusion layer. The gate electrode is comprised of semiconductor material such as polysilicon that is doped with impurities of the same conduction type as the first diffusion layer. The second diffusion layer is coupled only to the common contact.
摘要:
A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gate dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.
摘要:
A semiconductor memory device is provided, which makes it possible to increase the capacitance of capacitors in the capacitor section without degrading the withstand voltage of the capacitor dielectric. This device comprises a memory cell section including floating-gate type transistors and a capacitor section including capacitors. The memory cell section and the capacitor section are formed on a semiconductor substrate. Each of the transistors has a first gate dielectric, a floating gate, a second gage dielectric, and a control gate. Each of the capacitors has a lower electrode, a capacitor dielectric, and an upper electrode. A first part of the capacitors is/are designed to be applied with a first voltage and a second part thereof is/are applied with a second voltage on operation, where the first voltage is lower than the second voltage. Each of the first part of the capacitors has a recess formed on the lower electrode, thereby increasing its capacitance.