摘要:
In a semiconductor device of MOS structure, the element region has a shape such as a square shape which has a plurality of sides and a plurality of corners. On the element region, a conductive film which constitutes one electrode of the MOS structure is formed. The other electrode of the MOS structure is a silicon substrate. The conductive film is provided so as to cover at least sides adjacent to each other and so as not to cover the corners including the corners which are the contact points (intersecting points) of the adjacent sides. Further, in case the element region is in a ring shape, the conductive film is provided so as to cover none of the corners including the inside corners of the ring-shaped element region. By the above-mentioned structure, the occurrence of breakdown in the insulation film in the MOS structure can be prevented, and the reliability thereof can be enhanced.
摘要:
In a bit line contact section, a contact hole is formed through a silicon oxide film, and a contact plug made of a polysilicon film doped with impurities is buried in the contact hole. The silicon oxide film is formed with a wiring groove overlapping the contact hole. A bit line made of a metal film is buried in the wiring groove. The contact plug extends through the bit line, and has its upper surface substantially coplanar with an upper surface of the bit line. The contact plug is in contact with the bit line only on its side surfaces.
摘要:
A semiconductor device exhibits a stable driving force and high performance reliability. The semiconductor device has at least one transistor having a gate insulating film formed on a element region in a semiconductor substrate, a gate electrode formed on the gate insulating film, and a diffused layer in element regions on both sides of the gate electrode. The device also has a barrier insulating film formed so as to cover the transistor and the diffused layer. The height from a surface of the semiconductor substrate to the barrier insulating film is greater than the height from the surface, of the interface between the gate insulating film and the gate electrode.
摘要:
A semiconductor device exhibits a stable driving force and high performance reliability. The semiconductor device has at least one transistor having a gate insulating film formed on a element region in a semiconductor substrate, a gate electrode formed on the gate insulating film, and a diffused layer in element regions on both sides of the gate electrode. The device also has a barrier insulating film formed so as to cover the transistor and the diffused layer. The height from a surface of the semiconductor substrate to the barrier insulating film is greater than the height from the surface, of the interface between the gate insulating film and the gate electrode.
摘要:
A method of fabricating a semiconductor device which has a cell array with non-volatile memory transistors and a peripheral circuit including a first transistor and a second transistor as driven by a lower voltage than the first transistor is disclosed. The method includes the steps of forming over a semiconductor substrate a first gate dielectric film for use in the first transistor, selectively etching the first gate dielectric film in the cell array region to expose the substrate, forming over the exposed substrate a second gate dielectric film which is for use as a tunnel dielectric film of the memory transistors, forming a first gate electrode material film over the first and second gate dielectric films, selectively etching the first gate electrode material film and its underlying first gate dielectric film in the second transistor region, forming over the exposed substrate a third gate dielectric film which is for use in the second transistor, forming a second gate electrode material film over the third gate dielectric film, and forming gates of the respective transistors while letting the gates at least partly include the first and second gate electrode material films.
摘要:
In a nonvolatile semiconductor memory device, a charge accumulation layer is formed between adjacent two device isolation regions, at least a portion of the charge accumulation layer sandwiched with the device isolation regions has side walls each having a taper angle of 80 degrees or more and less than 90 degrees so that the charge accumulation layer at a lower end has a width wider than that at an upper end, a size of an opening of each of the device isolation regions is 0.25 &mgr;m or less, and a gate length of a memory cell is 0.2 &mgr;m or less.
摘要:
An electrically erasable programmable read-only memory is disclosed which has programmable memory cells connected to parallel bit lines provided above a semiconductor substrate. The memory cells include NAND cell blocks each of which has a series array of memory cell transistors. Parallel word lines are connected to the control gates of the memory cell transistors, respectively. In a data write mode, a selection transistor in a certain NAND cell block including a selected memory cell is rendered conductive to connect the certain cell block to a corresponding bit line associated therewith. Under such a condition, electrons are tunnel-injected into a floating gate of the selected memory cell transistor, and the threshold value of the certain transistor is increased to be a positive value. A logical data is thus written in the selected memory cell transistor. The data in the selected cell transistor is erased by discharging carriers accumulated in the floating gate thereof to its drain or the substrate, so that the threshold value of the certain transistor is decreased to be a negative value.
摘要:
The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite oepration, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
摘要:
The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite operation, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
摘要:
An EEPROM for storing multi-level data includes a memory cell array in which electrically erasable and programmable memory cells are arranged in matrix and each of the memory cells has at least three storage states, a write circuit for writing data to the memory cells, first and second write verify means each constituted of a sense amplifier, a data latch circuit and a detection circuit, for verifying an insufficient-written state of a memory cell and an excess-written state of a memory cell, respectively, an additional write circuit for additionally writing data to the memory cell in the insufficient-written state, and an additional erase circuit for additionally erasing data from the memory cell in the excess-written state.