Abstract: A multiport memory cell (200, 300, 600) includes a first word line (WL1) coupled to a gate electrode of a first transistor (201, 301, 601). A second word line (WL2) is coupled to a gate electrode of a second transistor (202, 302, 602). Importantly, the memory cell (200, 300, 600) includes a conductive path (215, 315) between an electrically floating body (426) of the first transistor (201) and an electrically floating body (426) of the second transistor (202). The first word line (WL1) may overlie a first portion of a common body (426) and the second word line (WL2) may overlie a second portion of the common body (426). The common body (426) may be positioned vertically between a buried oxide layer (427) and a gate dielectric layer (430) and laterally between first and second source/drain regions (401, 407) formed in a semiconductor layer (425).

Abstract: A one time programmable (OTP) memory has two-bit cells for increasing density. Each cell has two select transistors and a programmable transistor in series between the two select transistors. The programmable transistor has two independent storage locations. One is between the gate and a first source/drain region and the second is between the gate and a second source/drain region. The storage locations are portions of the gate dielectric where the sources or drains overlap the gate and are independently programmed by selectively passing a programming current through them. The programming current is of sufficient magnitude and duration to permanently reduce the impedance by more than three orders of magnitude of the storage locations to be programmed. The programming current is limited in magnitude to avoid damage to other circuit elements and is preferably induced at least in part by applying a negative voltage to the gate of the programming transistor.

Abstract: To increase the density of memory cells, a multibit memory cell (10, 50, 80, 110) can be manufactured by preventing the formation of at least one of the extension regions usually formed for the source or drain region. In one embodiment, a single mask (24) blocks the doping of the extension regions during ion implantation. If a tilt implantation process is used to form desired extension regions, two masks may be used. The process can also be integrated into a disposable spacer process. By blocking the extension region for a current electrode, a programmable region (32, 76, 102, 132) is formed adjacent a current electrode. The programmable region enables a two-bit memory cell to be formed.

Abstract: A non-volatile memory (NVM) array is made of NVM cells that have a floating gate transistor and a select transistor in which the floating gate transistor requires only a single layer of polysilicon. Adjacent cells are arranged so that the floating gates are staggered rather than being in the same line. This results in being able to put the cells closer together because of the reduction of the significance of what is commonly called poly-to-poly spacing. In this case, the termination of one floating gate is not lined-up with the floating gate of the adjacent NVM cell in the same row. Adjacent memory cells in the same column are made to have different configurations from each other which results in the floating gates in adjacent columns not being aligned, thus avoiding the poly-to-poly spacing limitation.

Abstract: A non-volatile memory (10) includes at least two buried bit lines (45, 47) formed within a semiconductor substrate (12), a charge storage layer (18) overlying the semiconductor substrate (12); a control gate (26) overlying the charge storage layer (18); an insulating liner (30) overlying the control gate; and first and second conductive sidewall spacer control gates (32, 34). Multiple programmable charge storage regions (42) and (41, 44) are created within the charge storage layer (18) beneath respective ones of the control gate (26) and the first and second sidewall spacer control gates (32, 34). Also, the non-volatile memory (10) is a virtual ground NOR type multi-bit flash EEPROM (electrically erasable programmable read only memory). By using conductive sidewall spacers as the control gates, a very dense multi-bit non-volatile memory can be manufactured.

Abstract: An active fuse includes an active fuse geometry (120) that is used to form both a variable resistor (106) and a select transistor (110). In one embodiment, the active fuse geometry is formed in a portion of an active region (160) of a semiconductor substrate (140), and a select gate (124) is disposed over an end portion (123) of the active fuse geometry to form an integral select transistor (110) for use in programming the active fuse. The use of a shared active fuse geometry within the active region allows for reduced area requirements and improved sensing margins.

Abstract: A semiconductor device (10) has a highly doped layer (26) having a first conductivity type uniformly implanted into the semiconductor substrate (20). An oxide-nitride-oxide structure (36, 38, 40) is formed over the semiconductor substrate (20). A halo region (46) having the first conductivity type is implanted at an angle in only a drain side of the oxide-nitride-oxide structure and extends under the oxide-nitride-oxide structure a predetermined distance from an edge of the oxide-nitride-oxide structure. A source (52) and drain (54) having a second conductivity type are implanted into the substrate (20). The resulting non-volatile memory cell provides a low natural threshold voltage to minimize threshold voltage drift during a read cycle. In addition, the use of the halo region (46) on the drain side allows a higher programming speed, and the highly doped layer (26) allows the use of a short channel device.

Abstract: An active fuse includes an active fuse geometry (120) that is used to form both a variable resistor (106) and a select transistor (110). In one embodiment, the active fuse geometry is formed in a portion of an active region (160) of a semiconductor substrate (140), and a select gate (124) is disposed over an end portion (123) of the active fuse geometry to form an integral select transistor (110) for use in programming the active fuse. The use of a shared active fuse geometry within the active region allows for reduced area requirements and improved sensing margins.

Abstract: A non-volatile memory having a thin film dielectric storage element is programmed by hot carrier injection (HCI) and erased by tunneling. The typical structure for the memory cells for this type of memory is silicon, oxide, nitride, oxide, and silicon (SONOS). The hot carrier injection provides relatively fast programming for SONOS, while the tunneling provides for erase that avoids the difficulties with the hot hole erase (HHE) type erase that generally accompanies hot carrier injection for programming. HHE is significantly more damaging to dielectrics leading to reliability issues. HHE also has a relatively narrow area of erasure that may not perfectly match the pattern for the HCI programming leaving an incomplete erasure. The tunnel erase effectively covers the entire area so there is no concern about incomplete erase. Although tunnel erase is slower than HHE, erase time is generally less critical in a system operation than is programming time.

Abstract: A semiconductor device (30) comprises an underlying insulating layer (34), an overlying insulating layer (42) and a charge storage layer (36) between the insulating layers (34, 42). The charge storage layer (36) and the overlying insulating layer (42) form an interface, where at least a majority of charge in the charge storage layer (36) is stored. This can be accomplished by forming a charge storage layer (36) with different materials such as silicon and silicon germanium layers or n-type and p-type material layers, in one embodiment. In another embodiment, the charge storage layer (36) comprises a dopant that is graded. By storing at least a majority of the charge at the interface between the charge storage layer (36) and the overlying insulating layer (42), the leakage of charge through the underlying insulating layer is decreased allowing for a thinner underlying insulating layer (34) to be used.

Abstract: A non-volatile multiple bit memory (10, 50) has electrically isolated storage elements (17, 21, 78, 80) that overlie a channel region having a central area (24, 94) with high impurity concentration. A planar gate (30, 84) overlies the storage elements. The high impurity concentration may be formed by a centrally located region (24) or by two peripheral regions (70, 72) having lower impurity concentration than the central portion of the channel. During a read or program operation, the channel area of high impurity concentration effectively controls a channel depletion region to enhance reading or programming of stored data bits. During a hot carrier program operation, the channel area of high impurity concentration enhances the programming efficiency by decreasing leakage currents in a memory array.

Abstract: A semiconductor device (10) has a highly doped layer (26) having a first conductivity type uniformly implanted into the semiconductor substrate (20). An oxide-nitride-oxide structure (36, 38, 40) is formed over the semiconductor substrate (20). A halo region (46) having the first conductivity type is implanted at an angle in only a drain side of the oxide-nitride-oxide structure and extends under the oxide-nitride-oxide structure a predetermined distance from an edge of the oxide-nitride-oxide structure. A source (52) and drain (54) having a second conductivity type are implanted into the substrate (20). The resulting non-volatile memory cell provides a low natural threshold voltage to minimize threshold voltage drift during a read cycle. In addition, the use of the halo region (46) on the drain side allows a higher programming speed, and the highly doped layer (26) allows the use of a short channel device.

Abstract: A memory device (70) that uses a non-volatile storage element (38), such as nitride, has reduced read disturb, which is the problem of tending to increase the threshold voltage of a memory device (70) during a read. To reduce this effect, the memory device (70) uses a counterdoped channel (86) to lower the natural threshold voltage of the device (70). This counterdoping can even be of sufficient dosage to reverse the conductivity type of the channel (86) and causing a negative natural threshold voltage. This allows for a lower gate voltage during read to reduce the adverse effect of performing a read. An anti-punch through (ATP) region (74) below the channel (86) allows for the lightly doped or reversed conductivity type channel (86) to avoid short channel leakage. A halo implant (46) on the drain side (54, 53) assists in hot carrier injection (HCI) so that the HCI is effective even though the channel (86) is lightly doped or of reversed conductivity type.

Abstract: A non-volatile multiple bit memory (10, 50) has electrically isolated storage elements (17, 21, 78, 80) that overlie a channel region having a central area (24, 94) with high impurity concentration. A planar gate (30, 84) overlies the storage elements. The high impurity concentration may be formed by a centrally located region (24) or by two peripheral regions (70, 72) having lower impurity concentration than the central portion of the channel. During a read or program operation, the channel area of high impurity concentration effectively controls a channel depletion region to enhance reading or programming of stored data bits. During a hot carrier program operation, the channel area of high impurity concentration enhances the programming efficiency by decreasing leakage currents in a memory array.

Abstract: A non-volatile memory having a thin film dielectric storage element is programmed by hot carrier injection (HCI) and erased by tunneling. The typical structure for the memory cells for this type of memory is silicon, oxide, nitride, oxide, and silicon (SONOS). The hot carrier injection provides relatively fast programming for SONOS, while the tunneling provides for erase that avoids the difficulties with the hot hole erase (HHE) type erase that generally accompanies hot carrier injection for programming. HHE is significantly more damaging to dielectrics leading to reliability issues. HHE also has a relatively narrow area of erasure that may not perfectly match the pattern for the HCI programming leaving an incomplete erasure. The tunnel erase effectively covers the entire area so there is no concern about incomplete erase. Although tunnel erase is slower than HHE, erase time is generally less critical in a system operation than is programming time.

Abstract: A semiconductor device (30) comprises an underlying insulating layer (34), an overlying insulating layer (42) and a charge storage layer (36) between the insulating layers (34, 42). The charge storage layer (36) and the overlying insulating layer (42) form an interface, where at least a majority of charge in the charge storage layer (36) is stored. This can be accomplished by forming a charge storage layer (36) with different materials such as silicon and silicon germanium layers or n-type and p-type material layers, in one embodiment. In another embodiment, the charge storage layer (36) comprises a dopant that is graded. By storing at least a majority of the charge at the interface between the charge storage layer (36) and the overlying insulating layer (42), the leakage of charge through the underlying insulating layer is decreased allowing for a thinner underlying insulating layer (34) to be used.