Abstract:
For fabricating a test field effect transistor on a semiconductor substrate, a layer of gate dielectric material is deposited on the semiconductor substrate, and a layer of gate electrode material is deposited on the layer of gate dielectric material. A dummy structure is formed on the gate electrode material, and the dummy structure is disposed over a shaped area of the gate electrode material and of the semiconductor substrate. The dummy structure has at least one sidewall around a perimeter of the shaped area. A spacer structure is formed to surround the at least one sidewall of the dummy structure outside of the perimeter of the shaped area. The dummy structure is etched away such that the shaped area of the gate electrode material is exposed and such that the spacer structure remains outside of the perimeter of the shaped area. Any exposed regions of the gate electrode material and of the gate dielectric material not under the spacer structure are etched away. The gate dielectric material remaining under the spacer structure forms a gate dielectric of the test field effect transistor, and the gate electrode material remaining under the spacer structure forms a gate electrode of the test field effect transistor. A drain and source dopant is implanted into exposed regions of the semiconductor substrate to form a first drain or source junction within the shaped area surrounded by the gate dielectric and the gate electrode, and to form a second drain or source junction outside the shaped area beyond the gate dielectric and the gate electrode. A width of the test field effect transistor is the perimeter of the shaped area, and a length of the test field effect transistor is the width of the gate dielectric and the gate electrode extending out from the perimeter of the shaped area.
Abstract:
An integrated circuit includes multiple active layers. Preferably, a semiconductor-on-insulator (SOI) or silicon-on-insulator wafer is utilized to house a first active layer. A second active layer is provided above an insulative layer above the SOI substrate. Solid phase epitaxy can be used to form the second active layer. Subsequent active layers can be added by a similar technique. A seeding window can also be utilized.
Abstract:
A silicon-on-insulator (SOI) chip. The SOI chip has a substrate; a buried oxide (BOX) layer disposed on the substrate; and an active layer disposed on the BOX layer, the active layer divided into a first and a second tile, the first tile having a first thickness and the second tile having a second thickness, the second thickness being smaller than the first thickness. Also disclosed is a method of fabricating a silicon-on-insulator (SOI) chip having an active layer with a non-uniform thickness. The method includes the steps of providing a substrate; providing a buried oxide layer (BOX) on the substrate; providing an active layer on the BOX layer, the active layer having an initially uniform thickness; dividing the active layer into at least a first and a second tile; and altering the thickness of the active layer in the area of the second tile.
Abstract:
For fabricating a field effect transistor on a semiconductor substrate in SOI (semiconductor on insulator) technology, an insulating block comprised of insulating material is formed on a thin semiconductor island comprised of semiconductor material. Semiconductor material is further grown from sidewalls of the semiconductor island to extend up along sidewalls of the insulating block to form a raised drain structure on a first side of the insulating block and the semiconductor island and to form a raised source structure on a second side of the insulating block and the semiconductor island. A drain and source dopant is implanted into the raised drain and source structures. A thermal anneal is performed to activate the drain and source dopant within the raised drain and source structures and such that the drain and source dopant extends partially into the semiconductor island. The insulating block is etched away to form a block opening, and a gate dielectric is deposited at a bottom wall of the block opening. The block opening is filled with a conductive material to form a gate structure disposed over the semiconductor island. The portion of the semiconductor island disposed under the gate structure forms a channel region that is fully depleted during operation of the field effect transistor. A drain silicide is formed within the raised drain structure, and a source silicide is formed within the raised source structure. In this manner, the drain and source silicides formed in the raised drain and source structures may be formed to have a higher thickness than the relatively thin semiconductor island to minimize series resistance at the drain and source of the field effect transistor.
Abstract:
An ultra-large-scale integrated (ULSI) circuit includes MOSFETs on an SOI substrate. The MOSFETs include elevated source and drain regions. The elevated source and drain regions are amorphized before doping. Neutral ion species can be utilized to amorphize the elevated source and drain region. Dopants are activated in a low-temperature rapid thermal anneal process.
Abstract:
For fabricating a field effect transistor on a semiconductor substrate in SOI (semiconductor on insulator) technology, a first layer of dielectric material is formed on the semiconductor substrate, and a layer of amorphous semiconductor material is deposited on the first layer of dielectric material. A second layer of dielectric material is deposited on the layer of amorphous semiconductor material, and a front gate opening is etched through the second layer of dielectric material to expose the layer of amorphous semiconductor material through the front gate opening. An amorphization dopant is implanted into the semiconductor substrate through the front gate opening to form a back gate region of amorphous semiconductor material in the semiconductor substrate such that the back gate region is formed to be aligned under the front gate opening. In addition, a back gate dopant is implanted into the back gate region of amorphous semiconductor material through the front gate opening. A gate dielectric is formed at the bottom of the front gate opening to contact the layer of amorphous semiconductor material, and a remaining portion of the front gate opening is filled with a gate electrode material. In this manner, because the same front gate opening is used for forming both the front gate electrode and the back gate region, the front gate electrode and the back gate region are substantially aligned with each other to ensure that the back gate region overlaps the front gate electrode. Thus, the area of the back gate region is minimized to be substantially aligned to the area of the channel region under the gate dielectric. A minimized area of the back gate region in turn minimizes the parasitic capacitance from the back gate region to enhance the speed performance of the MOSFET.
Abstract:
A lossless encoding methodology is described based on residual coding techniques and using a modified Least Mean Squares methodology to develop a predictor for a signal to be encoded, and a residual as the difference between the signal and its predicted value. After the residual for an input signal segment is obtained according to the method of the invention, that method is again applied to the residual value process to develop a second predictor, from which a second residual value is obtained. The method is then applied for at least one further iteration to the most recently obtained residual value process to develop a third predictor for the signal to be encoded. A single prediction value is then selected as a statistical representative of those multiple predictor values. The residual value to be used for encoding the input signal increment is determined as the difference between the signal value and the selected predictor value.
Abstract:
For fabricating a field effect transistor, a semiconductor pillar is formed on a layer of insulating material with a top surface and first and second side surfaces of the semiconductor pillar being exposed. A layer of dielectric material is formed on the top surface and the first and second side surfaces of the semiconductor pillar. A layer of conductive material is deposited on the layer of dielectric material on the top surface and the first and second side surfaces of the semiconductor pillar. A dummy dielectric structure is formed that covers a portion of the layer of conductive material such that a remaining portion of the layer of conductive material on the semiconductor pillar is exposed. The dummy dielectric structure has a predetermined sidewall on the layer of conductive material on the semiconductor pillar. A layer of hardmask dielectric is deposited on top and on the predetermined sidewall of the dummy dielectric structure and on the remaining portion of the layer of conductive material that is exposed. The layer of hardmask dielectric is anisotropically etched such that the hardmask dielectric remains at the predetermined sidewall of the dummy dielectric structure to form a spacer of hardmask dielectric. Any exposed region of the layer of conductive material and the layer of dielectric material not covered by the spacer of hardmask dielectric is etched away. The conductive material and the dielectric material that remain on the top surface and the first and second side surfaces at the gate portion of the semiconductor pillar form a three-sided gate structure and a three-sided gate dielectric of the field effect transistor for minimizing short channel effects in the field effect transistor.
Abstract:
A method of fabricating an integrated circuit with ultra-shallow source/drain junctions utilizes a dual amorphization technique. The technique creates a shallow amorphous region and a deep amorphous region. The shallow amorphous region is between 10-15 nm below the top surface of the substrate, and the deep amorphous region is between 150-200 nm below the top surface of the substrate. The process can be utilized for P-channel or N-channel metal oxide semiconductor field effect transistors (MOSFETs). In the case of a P-channel MOSFET, a nitrogen barrier is formed in the P-channel gate prior to p+ doping. Annealing the gate conductor is done in a step separate from the source/drain region annealing step.
Abstract:
An integrated circuit includes multiple active layers. Preferably, a semiconductor-on-insulator (SOI) or silicon-on-insulator wafer is utilized to house a first active layer. A second active layer is provided by bonding a bulk substrate to the SOI substrate and removing the bulk substrate to leave a thin semiconductor layer. Subsequent active layers can be added by a similar technique. Preferably, the bulk substrates utilize a hydrogen implant to provide a breaking interface.