摘要:
The present invention provides a redundancy circuit in a semiconductor memory device which has spare memory cells which can store information that can be substituted for data of defective memory cells after the completion of the manufacturing process. If addresses designating the defective memory cells are externally input, the redundancy circuit generates a defective cell relief address signal which corresponds to the address designating the defective memory cell and is used to prevent defective data stored in normal memory cells from being output and causes correction data, to be substituted for the defective data output in correspondence with the defective cell relief address.
摘要:
A nonvolatile semiconductor integrated circuit having a cell array consisting of a plurality of memory strings each having first to N-th (N=2, 3, 4, . . . ) memory cell transistors of a NAND structure includes a plurality of first string select transistors connected in series to the first memory cell transistor, and a plurality of second string select transistors connected in series to the N-th memory cell transistor. One of the string select transistors serially connected to the first and N-th memory cell transistors has a control terminal connected to a ground connecting point, thus to have a ground select function as well as a string select function.
摘要:
A nonvolatile semiconductor memory with a unit cell structure suitable for high speed operation and a low power supply voltage. The nonvolatile semiconductor memory includes a switching circuit including block select transistors connected by its respective terminal to a corresponding bit line. This switching circuit transmits a signal only when a string to which the switching circuit corresponds is selected. A second active region having a different impurity concentration from a first active region constituting source and drain regions of memory transistors is formed at a substrate contact portion of a bit line contact portion where the memory string and bit line are connected. The impurity concentration of the second active region is lower than that of the first active region.
摘要:
A nonvolatile semiconductor memory with a unit cell structure suitable for high speed operation and a low power supply voltage. The nonvolatile semiconductor memory includes a switching circuit including block select transistors connected by its respective terminal to a corresponding bit line. This switching circuit transmits a signal only when a string to which the switching circuit corresponds is selected. A second active region having a different impurity concentration from a first active region constituting source and drain regions of memory transistors is formed at a substrate contact portion of a bit line contact portion where the memory string and bit line are connected. The impurity concentration of the second active region is lower than that of the first active region.
摘要:
A fuse circuit according to the present invention includes first and second fuses, each of which has a first end and a second end. The first and second ends of the first fuse are connected in a straight line. The first end of the second fuse is spaced by a first interval from the first end of the first fuse, and the second end thereof is spaced by a second interval from the second end of the first fuse. The first ends of the first and second fuses have the same widths as those of the second ends thereof. Alternatively, the first ends of the first and second fuses have narrower widths that those of the second ends thereof.
摘要:
There is provided an internal voltage generating circuit that reliably supplies a constant internal voltage to the interior of a semiconductor device without regard to an external voltage, where the internal voltage generating circuit compares a first reference voltage with a first internal voltage fed back to generate the first internal voltage following the first reference voltage, receives the first internal voltage to generate a second reference voltage which is more insensitive to fluctuation of the external voltage than the first reference voltage, and compares the second reference voltage with a second internal voltage fed back to generate the second internal voltage which follows the second reference voltage and has a variation gradient smaller than that of the first internal voltage when the external voltage is changed, thereby supplying the second internal voltage to a circuit requiring stabilized internal voltage, which is obtained to increase stability and durability of the operation of the semiconductor device.
摘要:
There is provided an internal voltage generating circuit that reliably supplies a constant internal voltage to the interior of a semiconductor device without regard to an external voltage, where the internal voltage generating circuit compares a first reference voltage with a first internal voltage fed back to generate the first internal voltage following the first reference voltage, receives the first internal voltage to generate a second reference voltage which is more insensitive to fluctuation of the external voltage than the first reference voltage, and compares the second reference voltage with a second internal voltage fed back to generate the second internal voltage which follows the second reference voltage and has a variation gradient smaller than that of the first internal voltage when the external voltage is changed, thereby supplying the second internal voltage to a circuit requiring stabilized internal voltage, which is obtained to increase stability and durability of the operation of the semiconductor device.