Abstract: A plasma etching system having a wafer chuck with a magnet that applies a magnetic field over a wafer to shield the wafer from charged particles. The magnetic field is parallel with the wafer, and is strongest near the wafer surface. The magnetic field may be straight, or circular. In operation, electrons are deflected from the wafer by the Lorentz force, the wafer acquires a positive charge, and ions are deflected by electrostatic repulsion. Neutral species are allowed through the magnetic field, and they collide with the wafer. Neutral species generally provide more isotropic and material-selective etching than charged particles, so the present magnetic field tends to increase etch isotropy and material selectivity. Also, the magnetic field can protect the wafer from seasoning processes designed to clean unwanted films from the chamber surface as seasoning processes typically rely on etching by charged particles.

Abstract: A method of forming a wiring structure for an integrated circuit includes the steps of forming a plurality of features in a layer of dielectric material, and forming spacers on sidewalls of the features. Conductors are then formed in the features, being separated from the sidewalls by the spacers. The spacers are then removed, forming air gaps at the sidewalls so that the conductors are separated from the sidewalls by the air gaps. Dielectric layers above and below the conductors may be low-k dielectrics having a dielectric constant less than that of the dielectric between the conductors. A cross-section of each of the conductors has a bottom in contact with the a low-k dielectric layer, a top in contact with another low-k dielectric, and sides in contact only with the air gaps. The air gaps serve to reduce the intralevel capacitance.

Abstract: A array of multi-bit Read Only Memory (ROM) cells is in a semiconductor substrate of a first conductivity type with a first concentration. Each ROM cell has a first and second regions of a second conductivity type spaced apart from one another in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. Each ROM cell has one of a plurality of N possible states, where N is greater than 2. The state of each ROM cell is determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.

Abstract: A method of forming a wiring structure for an integrated circuit includes the steps of forming a plurality of features in a layer of dielectric material, and forming spacers on sidewalls of the features. Conductors are then formed in the features, being separated from the sidewalls by the spacers. The spacers are then removed, forming air gaps at the sidewalls so that the conductors are separated from the sidewalls by the air gaps. Dielectric layers above and below the conductors may be low-k dielectrics having a dielectric constant less than that of the dielectric between the conductors. A cross-section of each of the conductors has a bottom in contact with the a low-k dielectric layer, a top in contact with another low-k dielectric, and sides in contact only with the air gaps. The air gaps serve to reduce the intralevel capacitance.

Abstract: A bi-directional read/program non-volatile memory cell and array is capable of achieving high density. Each memory cell has two spaced floating gates for storage of charges thereon. The cell has spaced apart source/drain regions with a channel therebetween, with the channel having three portions. One of the floating gate is over a first portion; another floating gate is over a second portion, and a gate electrode controls the conduction of the channel in the third portion between the first and second portions. A control gate is connected to each of the source/drain regions, and is also capacitively coupled to the floating gate. The cell programs by hot channel electron injection, and erases by Fowler-Nordheim tunneling of electrons from the floating gate to the gate electrode. Bi-directional read permits the cell to be programmed to store bits, with one bit in each floating gate.

Abstract: A method of forming a floating gate memory cell array, and the array formed thereby, wherein a trench is formed into the surface of a semiconductor substrate. The source and drain regions are formed underneath the trench and along the substrate surface, respectively, with a non-linear channel region therebetween. The floating gate has a lower portion disposed in the trench and an upper portion disposed above the substrate surface and having a lateral protrusion extending parallel to the substrate surface. The lateral protrusion is formed by etching a cavity into an exposed end of a sacrificial layer and filling it with polysilicon. The control gate is formed about the lateral protrusion and is insulated therefrom. The trench sidewall meets the substrate surface at an acute angle to form a sharp edge that points toward the floating gate and in a direction opposite to that of the lateral protrusion.

Abstract: A array of multi-bit Read Only Memory (ROM) cells is in a semiconductor substrate of a first conductivity type with a first concentration. Each ROM cell has a first and second regions of a second conductivity type spaced apart from one another in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. Each ROM cell has one of a plurality of N possible states, where N is greater than 2. The state of each ROM cell is determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.

Abstract: A nonvolatile memory cell having a floating gate for the storage of charges thereon has a control gate and a separate erase gate. The cell is programmed by hot channel electron injection and is erased by poly to poly Fowler-Nordheim tunneling. A method for making an array of unidirectional cells in a planar substrate, as well as an array of bidirectional cells in a substrate having a trench, is disclosed. An array of such cells and a method of making such an array is also disclosed.

Abstract: A system and method for aligning a wafer in an exposure apparatus includes a holder adapted to hold a wafer (the wafer includes alignment marks), a coarse alignment system, and a fine alignment system having a higher precision than the coarse alignment system. The fine alignment system includes multiple optical detectors. Each of the optical detectors is positioned to detect a corresponding alignment mark on the wafer. An alignment processor is connected to and controls the optical detectors and the holder. The optical detectors are controlled by the alignment processor to simultaneously detect the alignment marks in parallel operations. Further, the alignment processor simultaneously processes signals from the optical detectors in parallel operations.

Abstract: A method of forming an array of floating gate memory cells, and an array formed thereby, wherein a trench is formed into a surface of a semiconductor substrate. The source region is formed underneath the trench, the drain region is formed along the substrate surface, and the channel region therebetween includes a first portion extending vertically along the trench sidewall and a second portion extending horizontally along the substrate surface. The floating gate is disposed in the trench adjacent to and insulated from the channel region first portion. The control gate is disposed over and insulated from the channel region second portion. The trench sidewall meets the substrate surface at an acute angle to form a sharp edge. The channel region second portion extends from the second region in a direction toward the sharp edge and the floating gate to define a path for programming the floating gate with electrons via hot electron injection.

Abstract: A bi-directional read/program non-volatile memory cell and array is capable of achieving high density. Each memory cell has two spaced floating gates for storage of charges thereon. The cell has spaced apart source/drain regions with a channel therebetween, with the channel having three portions. One of the floating gate is over a first portion; another floating gate is over a second portion, and a gate electrode controls the conduction of the channel in the third portion between the first and second portions. A control gate is connected to each of the source/drain regions, and is also capacitively coupled to the floating gate. The cell programs by hot channel electron injection, and erases by Fowler-Nordheim tunneling of electrons from the floating gate to the gate electrode. Bi-directional read permits the cell to be programmed to store bits, with one bit in each floating gate.

Abstract: An array of phase changing memory cells that includes a current source, a voltage sensor, a plurality of conductive bit lines electrically connected to the current source, a plurality of conductive word lines each electrically connected to a ground plane via a first resistor and to the voltage sensor, and a plurality of memory cells. Each memory cell is connected between one of the bit lines and one of the word lines and includes phase change memory material. One of the memory cells is selected by turning on switches just on the bit line and word line connected thereto, or by turning a switch connected in series between the corresponding bit and word lines, where the read current flows through the selected memory cell and the voltage sensor measures a voltage drop across the selected memory cell.

Abstract: A array of multi-bit Read Only Memory (ROM) cells is in a semiconductor substrate of a first conductivity type with a first concentration. Each ROM cell has a first and second regions of a second conductivity type spaced apart from one another in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. Each ROM cell has one of a plurality of N possible states, where N is greater than 2. The state of each ROM cell is determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.

Abstract: A phase changing memory device, and method of making the same, that includes programmable memory material disposed between a pair of electrodes. The programmable memory material includes discrete layers of phase change material, separated by conductive interface layers, that exhibits relatively stable resistivity values over discrete ranges of crystallizing and amorphousizing thermal pulses applied thereto, for multi-bit storage. The memory material and one of the electrodes can be disposed along spacer material surfaces to form an electrical current path that narrows in width as the current path approaches the other electrode, such that electrical current passing through the current path generates heat for heating the memory material disposed between the electrodes.

Abstract: A non-volatile memory cell has a single crystalline semiconductive material, such as single crystalline silicon, of a first conductivity type. A first and a second region each of a second conductivity type, different from the first conductivity type, spaced apart from one another is formed in the semiconductive material. A channel region, having a first portion, and a second portion, connects the first and second regions for the conduction of charges. A dielectric is on the channel region. A floating gate, which can be conductive or non-conductive, is on the dielectric, spaced apart from the first portion of the channel region. The first portion of the channel region is adjacent to the first region, with the first floating gate having generally a triangular shape. The floating gate is formed in a cavity. A gate electrode is capacitively coupled to the first floating gate, and is spaced apart from the second portion of the channel region.

Abstract: An array of floating gate memory cells, and a method of making same, where each pair of memory cells includes a pair of trenches formed into a surface of a semiconductor substrate, with a strip of the substrate disposed therebetween, a source region formed in the substrate strip, a pair of drain regions, a pair of channel regions each extending between the source region and one of the drain regions, a pair of floating gates each disposed in one of the trenches, and a pair of control gates. Each channel region has a first portion disposed in the substrate strip and extending along one of the trenches, a second portion extending underneath the one trench, a third portion extending along the one trench, and a fourth portion extending along the substrate surface and under one of the control gates.

Abstract: An array of phase changing memory cells that includes a current source, a voltage sensor, a plurality of conductive bit lines electrically connected to the current source, a plurality of conductive word lines each electrically connected to a ground plane via a first resistor and to the voltage sensor, and a plurality of memory cells. Each memory cell is connected between one of the bit lines and one of the word lines and includes phase change memory material. One of the memory cells is selected by turning on switches just on the bit line and word line connected thereto, or by turning a switch connected in series between the corresponding bit and word lines, where the read current flows through the selected memory cell and the voltage sensor measures a voltage drop across the selected memory cell.

Abstract: A stacked gate nonvolatile memory floating gate device has a control gate. Programming of the cell in the array is accomplished by hot channel electron injection from the drain to the floating gate. Erasure occurs by Fowler-Nordheim tunneling of electrons from the floating gate to the control gate. Finally, to increase the density, each cell can be made in a trench.

Abstract: A method of forming an array of floating gate memory cells, and an array formed thereby, wherein a trench is formed into a surface of a semiconductor substrate. The source region is formed underneath the trench, the drain region is formed along the substrate surface, and the channel region therebetween includes a first portion extending vertically along the trench sidewall and a second portion extending horizontally along the substrate surface. The floating gate is disposed in the trench adjacent to and insulated from the channel region first portion. The control gate is disposed over and insulated from the channel region second portion. The trench sidewall meets the substrate surface at an acute angle to form a sharp edge. The channel region second portion extends from the second region in a direction toward the sharp edge and the floating gate to define a path for programming the floating gate with electrons via hot electron injection.

Abstract: A multi-bit Read Only Memory (ROM) cell has a semiconductor substrate of a first conductivity type with a first concentration. A first and second regions of a second conductivity type spaced apart from one another are in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. The ROM cell has one of a plurality of N possible states, where N is greater than 2. The possible states of the ROM cell are determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.