摘要:
In accordance with the invention a high-k gate dielectric is formed by the steps of first forming a silicon oxide layer over a silicon substrate and then exposing the silicon oxide to a flux of low energy plasma containing metal ions which, when inserted into silicon oxide, form a high-k dielectric material suitable for use as a high-k gate dielectric. In one embodiment, the silicon oxide is exposed to a first plasma containing a first species of metal ions and then to a plasma of another species of metal ions which, when inserted into the silicon oxide with the metal ions in the first plasma, further increase the dielectric constant of the silicon oxide.
摘要:
A method of forming a narrow isolation structure in a semiconducting substrate. The isolation structure is a trench that has a bottom and sidewalls, and that is to be filled with an isolating material. The isolating material has desired electrical properties and desired chemical properties, and is substantially reactively grown from the semiconducting substrate. A precursor material layer is formed on the bottom of the trench and on the sidewalls of the trench. The precursor material layer has electrical properties and chemical properties that are substantially similar to the desired electrical properties and the desired chemical properties of the isolating material. A substantial portion of the precursor material layer is removed from the bottom of the trench to expose the semiconducting substrate at the bottom of the trench, while leaving a substantial portion of the precursor material layer on the sidewalls of the trench. The isolating material is reactively grown in the trench, where the isolating material preferentially grows from the exposed semiconducting substrate at the bottom of the trench at a first rate. The precursor material layer at least partially inhibits formation of the isolating material from the semiconducting substrate at the sidewalls of the trench. The isolating material forms from the sidewalls of the trench at a second rate, where the first rate is substantially higher than the second rate. Thus, by forming a precursor layer that inhibits formation of the isolation material at the sidewalls of the trench, the isolation material preferentially grows from the bottom of the trench rather than expanding sideways from the sidewalls of the trench, which tends to widen the isolation structure. Because the precursor layer has properties that are substantially similar to those that are desired in the isolation material, the precursor layer remains at the sidewalls of the trench near the edge of the isolation structure. Therefore, the isolation structure functions as desired, but is narrower than it otherwise would be, if the precursor layer had not been formed.
摘要:
A process for inhibiting the passage of dopant from a gate electrode into a thin gate oxide comprises nitridation of the upper surface of the thin gate oxide, prior to formation of the gate electrode over the gate oxide, to thereby form a barrier of nitrogen atoms in the upper surface region of the gate oxide adjacent the interface between the gate oxide and the gate electrode to inhibit passage of dopant atoms from the gate electrode into the thin gate oxide during annealing of the structure. In one embodiment, a selective portion of silicon oxide on a silicon substrate may be etched to thin the oxide to the desired thickness using a nitrogen plasma with a bias applied to the silicon substrate. Nitridation of the surface of the etched silicon oxide is then carried out in the same apparatus by removing the bias from the silicon substrate.
摘要:
An isolation trench in a silicon semiconductor substrate is provided with a barrier region containing nitrogen atoms formed in the trench, contiguous with the silicon semiconductor substrate surfaces of the trench. The novel isolation trench structure of the invention is formed by forming an isolation trench in a silicon semiconductor substrate; forming in the isolation trench a barrier region by treating the trench structure with nitrogen atoms from a nitrogen plasma; and then forming a silicon oxide layer over the barrier region in the trench to confine the nitrogen atoms in the barrier region. In a preferred embodiment, a silicon oxide liner is first formed over the silicon semiconductor substrate surfaces of the trench, and then the trench structure is treated with nitrogen atoms from a nitrogen plasma to form, on the silicon semiconductor substrate surfaces of the trench, a barrier layer which contains silicon atoms, oxygen atoms, and nitrogen atoms.
摘要:
A process for etching oxide is disclosed wherein a reproducibly accurate and uniform amount of silicon oxide can be removed from a surface of an oxide previously formed over a semiconductor substrate by exposing the oxide to a nitrogen plasma in an etch chamber while applying an rf bias to a substrate support on which the substrate is supported in the etch chamber. The thickness of the oxide removed in a given period of time may be changed by changing the amount of rf bias applied to the substrate through the substrate support.
摘要:
A method of forming a supersaturated layer on a semiconductor device, where an initial phase layer is deposited on the semiconductor device. The initial phase layer has a solid phase dopant saturation level and a liquid phase dopant saturation level, where the liquid phase dopant saturation level is greater than the solid phase dopant saturation level. A concentration of a dopant is impregnated within the initial phase layers, where the concentration of the dopant is greater than the solid phase dopant saturation level and no more than about the liquid phase dopant saturation level. The initial phase layer is annealed, without appreciably heating the semiconductor device, using an amount of energy that is high enough to liquefy the initial phase layer over a melt duration. This dissolves the dopant in the liquefied initial phase layer. The amount of energy is low enough to not appreciably gasify or ablate the initial phase layer. The liquefied initial phase layer is cooled to freeze the dissolved dopant in a supersaturated, electrically activated concentration, thereby forming the supersaturated layer. An initial phase layer of either polysilicon or amorphous silicon may be deposited over a CMOS device. After laser annealing the initial phase layer with a melt duration of no more than about 100 nanoseconds, it is transformed into a doped polysilicon gate electrode that can be patterned and further processed.
摘要:
A method of forming a narrow isolation structure in a semiconducting substrate. The isolation structure is a trench that has a bottom and sidewalls, and that is to be filled with an isolating material. The isolating material has desired electrical properties and desired chemical properties, and is substantially reactively grown from the semiconducting substrate. A precursor material layer is formed on the bottom of the trench and on the sidewalls of the trench. The precursor material layer has electrical properties and chemical properties that are substantially similar to the desired electrical properties and the desired chemical properties of the isolating material. A substantial portion of the precursor material layer is removed from the bottom of the trench to expose the semiconducting substrate at the bottom of the trench, while leaving a substantial portion of the precursor material layer on the sidewalls of the trench. The isolating material is reactively grown in the trench, where the isolating material preferentially grows from the exposed semiconducting substrate at the bottom of the trench at a first rate. The precursor material layer at least partially inhibits formation of the isolating material from the semiconducting substrate at the sidewalls of the trench. The isolating material forms from the sidewalls of the trench at a second rate, where the first rate is substantially higher than the second rate. Thus, by forming a precursor layer that inhibits formation of the isolation material at the sidewalls of the trench, the isolation material preferentially grows from the bottom of the trench rather than expanding sideways from the sidewalls of the trench, which tends to widen the isolation structure. Because the precursor layer has properties that are substantially similar to those that are desired in the isolation material, the precursor layer remains at the sidewalls of the trench near the edge of the isolation structure. Therefore, the isolation structure functions as desired, but is narrower than it otherwise would be, if the precursor layer had not been formed.
摘要:
A process is described for using a silicon layer as an implant and out-diffusion layer, for forming defect-free source/drain regions in a semiconductor substrate, and also for subsequent formation of silicon nitride spacers. A nitrogen-containing dopant barrier layer is first formed over a single crystal semiconductor substrate by nitridating either a previously formed gate oxide layer, or a silicon layer formed over the gate oxide layer, to form a barrier layer comprising either a silicon, oxygen, and nitrogen compound or a compound of silicon and nitrogen. The nitridating may be carried out using a nitrogen plasma followed by an anneal. A polysilicon gate electrode is then formed over this barrier layer, and the exposed portions of the barrier layer remaining are removed. An amorphous silicon layer of predetermined thickness is then formed over the substrate and polysilicon gate electrode. This amorphous layer is then implanted with a dopant capable of forming a source/drain region in the underlying silicon substrate by subsequent diffusion of the implanted dopant from the amorphous silicon layer into the substrate. The structure is then annealed to diffuse the dopant from the implanted silicon layer into the substrate to form the desired source/drain regions and into the polysilicon gate electrode to dope the polysilicon. The annealing further serves to cause the amorphous silicon layer to crystalize to polycrystalline silicon (polysilicon). In one embodiment, the polysilicon layer is then nitridized to convert it to a silicon nitride layer which is then patterned to form silicon nitride spacers on the sidewalls of the polysilicon gate electrode to electrically insulate the gate electrode from the source/drain regions. The process may be further modified to also create LDD or HDD source/drain regions in the substrate (depending on the concentration of the dopant), using multiple implants into the same silicon layer or by the sequential use of several silicon layers, each of which is used as an implantation and out-diffusion layer.
摘要:
A device can include a controller interface having at least one controller data output configured to output read data, and at least one controller data input configured to receive write data; and a memory device interface having a write data output configured to transmit the write data on rising and falling edges of a periodic signal, and a read data input configured to receive the read data at a same transmission rate as the write data.
摘要:
Methods for fabricating diffusion regions having steep concentration profiles within MOS devices while minimizing junction capacitance degradation are provided. In particular, methods are provided which include patterning a gate structure upon a semiconductor substrate and subsequently etching a recess in exposed portions of the substrate. In some cases, the method includes forming a first dopant region within the exposed portions prior to etching the recess. The method may additionally or alternatively include implanting a second set of dopants into portions of the semiconductor substrate bordering the recess. In either case, the method includes growing an epitaxial layer within the recess and implanting a third set of dopants into the semiconductor topography to form a second dopant region extending to a depth at least within the epitaxial layer. A resulting semiconductor topography includes a source/drain region comprising an upper portion consisting essentially of first dopants of a first conductivity type.