What is claimed is:
1. An insulated-gate field-effect transistor comprising:
first and second impurity regions placed so as to oppose each other;
a strained silicon layer having a channel between both the first and second impurity regions;
a gate insulator placed at least in a region corresponding to the channel, on top of the strained silicon layer; and
a gate electrode on top of the gate insulator, wherein a region of the strained silicon layer, corresponding to the channel, does not have a silicon germanium layer in contact therewith, and the strained silicon layer, in regions other than the region corresponding to the channel, have regions where the silicon germanium layer is in contact therewith.
2. An insulated-gate field-effect transistor according to claim 1, wherein a source electrode and drain electrode in contact with the first and second impurity regions, respectively, include a silicon germanium layer in contact with the strained silicon layer.
3. An insulated-gate field-effect transistor according to claim 1, wherein the strained silicon layer is placed in the upper part of a substrate and the silicon germanium layer does not exist in the region of the strained silicon layer, corresponding to at least the channel, and on a side adjacent to the substrate.
4. An insulated-gate field-effect transistor according to claim 1, wherein the strained silicon layer is placed in the upper part of a substrate and a void exists in a region on a side adjacent to the substrate, opposite from a face of the strained silicon layer, corresponding to at least the channel.
5. An insulated-gate field-effect transistor according to claim 1, wherein the strained silicon layer is placed in the upper part of a substrate and an insulating film exists in a region on a side adjacent to the substrate, opposite from a face of the strained silicon layer, corresponding to at least the channel.
6. An insulated-gate field-effect transistor according to claim 1, wherein a portion of the region of the strained silicon layer, corresponding to the channel, does not have a silicon germanium layer in contact therewith.
7. A semiconductor device having an insulated-gate field-effect transistor comprising:
first and second impurity regions placed so as to oppose each other;
a strained silicon layer having a channel between both the first and second impurity regions;
a gate insulator placed at least in a region corresponding to the channel, on top of the strained silicon layer; and a gate electrode on top of the gate insulator, wherein a region of the strained silicon layer, corresponding to the channel, does not have a silicon germanium layer in contact therewith, and the strained silicon layer, in regions other than the region corresponding to the channel, have regions where the silicon germanium layer is in contact therewith, and an insulated-gate field-effect transistor comprising:
first and second impurity regions placed so as to oppose each other;
a strained silicon layer having a channel between both the first and second impurity regions;
a gate insulator placed at least in a region corresponding to the channel, on top of the strained silicon layer; and
a gate electrode on top of the gate insulator, wherein a portion of a region of the strained silicon layer, corresponding to the channel, does not have a silicon germanium layer in contact therewith;
said insulated-gate field-effect transistors being formed on the same support substrate.
8. An insulated-gate field-effect transistor comprising:
a support substrate;
a bar-shaped strained silicon layer on the support substrate;
a gate insulator formed so as to spread across the upper surface of the bar-shaped strained silicon layer, in the direction orthogonal to the longitudinal direction thereof, covering at least a part of both sides of the bar-shaped strained silicon layer;
a gate electrode formed on the gate insulator; and
a source region and drain region placed in regions positioned on opposite sides of the gate electrode, respectively, along the longitudinal direction of the bar-shaped strained silicon layer, wherein a channel is formed in a portion of the bar-shaped strained silicon layer, corresponding to a region on the underside of the gate electrode, in such a way as to extend along the longitudinal direction of the bar-shaped strained silicon layer.
9. An insulated-gate field-effect transistor according to claim 8, wherein the gate electrode is formed on the gate insulator on the sides of two faces of the bar-shaped strained silicon layer, intersecting the support substrate and extending along the longitudinal direction of the bar-shaped strained silicon layer, respectively.
10. An insulated-gate field-effect transistor according to claim 8, having a silicon germanium layer in contact with the bar-shaped strained silicon layer at opposite ends of the bar-shaped strained silicon layer, in the longitudinal direction thereof and under a region where the channel does not exists.
11. An insulated-gate field-effect transistor according to claim 8, wherein a plurality of the bar-shaped strained silicon layers are provided and a set of the source region and drain region is formed such that the source region and drain region are common to the plurality of the bar-shaped strained silicon layers, and are connected to a plurality of channels.
12. An insulated-gate field-effect transistor comprising:
a support substrate;
a plurality of bar-shaped strained silicon layers disposed with longitudinal sides thereof, opposed to each other, on the support substrate;
a plurality of bar-shaped silicon germanium layers each disposed between adjacent layers of the plurality of the bar-shaped strained silicon layers;
a gate insulator formed so as to spread across the longitudinal sides of the plurality of the bar-shaped strained silicon layers; and the plurality of the bar-shaped silicon germanium layers;
gate electrodes formed on the gate insulator; and
a source region and drain region formed in regions on opposite sides of the respective gate electrodes, respectively, along the longitudinal direction of the plurality of the bar-shaped strained silicon layers; and the plurality of the bar-shaped silicon germanium layers, wherein a channel is formed in regions of the plurality of the bar-shaped strained silicon layers, corresponding to the underside of the respective gate electrodes, and on the side away from the support substrate.
13. An insulated-gate field-effect transistor according to claim 12, wherein a channel is formed on the sides of two faces of the respective bar-shaped strained silicon layers, along the direction intersecting the support substrate, respectively.
14. An insulated-gate field-effect transistor according to claim 12, wherein the source region and drain region are connected to a plurality of channel regions common to the plurality of the bar-shaped strained silicon layers, respectively.
15. An insulated-gate field-effect transistor according to claim 8, wherein the support substrate is a substrate the top surface of which has direction of crystal plane (100), and the longitudinal direction of the bar-shaped strained silicon layer is substantially parallel to a direction <100> of the support substrate.
16. An insulated-gate field-effect transistor according to claim 11, wherein the support substrate is a substrate the top surface of which has direction of crystal plane (100), and the longitudinal direction of the bar-shaped strained silicon layers is substantially parallel to a direction <100> of the support substrate.
17. An insulated-gate field-effect transistor according to claim 8, wherein the support substrate is a substrate the top surface of which has direction of crystal plane (100), and the longitudinal direction of the bar-shaped strained silicon layer is substantially parallel to a direction <110> of the support substrate.
18. An insulated-gate field-effect transistor according to claim 11, wherein the support substrate is a substrate the top surface of which has direction of crystal plane (100), and the longitudinal direction of the bar-shaped strained silicon layers is substantially parallel to a direction <110> of the support substrate.
19. A method of fabricating an insulated-gate field-effect transistor comprising the steps of:
preparing a silicon substrate;
forming an oxide film on the surface of the silicon substrate;
defining an opening by etching a portion of the oxide film; implanting ions into the opening;
causing silicon germanium seed crystals to grow in the opening;
depositing amorphous silicon germanium on top of the opening and the oxide film;
heating the amorphous silicon germanium to be turned into silicon germanium crystals; and
depositing a strained silicon layer on top of the silicon germanium crystals.
20. A method of fabricating an insulated-gate field-effect transistor comprising the steps of:
preparing a silicon substrate;
forming an oxide film on the surface of the silicon substrate;
defining an opening by etching a portion of the oxide film;
causing silicon germanium seed crystals to grow in the opening;
oxidizing the surface of the silicon germanium seed crystals;
subjecting the silicon germanium seed crystals to high-temperature heat treatment;
removing an oxide film on the surface of the silicon germanium seed crystals;
depositing amorphous silicon germanium on top of the opening and the oxide film;
heating the amorphous silicon germanium to be turned into silicon germanium crystals; and
depositing a strained silicon layer on top of the silicon germanium crystals.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Method for detecting and extracting fileprints, comprising the steps of:
inputting a data sequence;
obtaining parsing parameters from a secure key and selecting parameters for said secure key, wherein said selecting parameters is initiated by the selection of an integer N, said integer N being both a fixed value and a power of 2;
partitioning said data sequence into segments using said parsing parameters;
estimating a power spectral density of said segments, wherein each said segment comprises N-samples;
ABC-processing each of said segments using ABC-parameters;
generating fileprints by threshold-detection-comparing said ABC-processed segments to thresholds from said secure key;
compressing and encoding said fileprints so as to reduce their size; and
extracting and outputting said compressed and encoded fileprints.
2. Method of claim 1, wherein said step of estimating the power spectral density further comprises the step of performing a fast fourier transform (FFT).
3. Method of claim 1, wherein said step of selecting parameters further comprises selecting parsing, ABC, and threshold parameters.
4. Method for storing and retrieving files using a detector and extractor of fileprints (DEF), comprising the steps of:
compressing and encoding an input data file;
a first step of selecting either said input data file or said compressed and encoded input data file to be sent to a router for storage;
sending said selected file to a router for storage;
a second step of selecting fileprint extraction from either said input data file or said compressed and encoded input data file;
a first step of storing on a first storagesystem network, comprising:
storing a statusoutcome of said first step of selecting;
storing said fileprints;
storing DEF parameters, and input data file identification; and
a second step of storing on a second storagesystem network, comprising:
storing said statusoutcome of said second step of selecting;
storing a version of said selected file from a router, and
storing input data file identification;
requesting a retrieval by identifying said stored file;
a first step of retrieving from a first storagesystem network said stored file and said statusoutcome of said first step of selecting;
decompressing and decoding said retrieved said stored file;
a second step of retrieving from said second storagesystem network, comprising:
retrieving said statusoutcome of said second step of selecting;
retrieving said fileprints of said stored file, and
retrieving said DEF parameters associated with said stored file;
directing said DEF parameters to said DEF;
a first step of directing said statusoutcome of said second step of selecting so as to determine whether a step of said decompressing and decoding will output either a decompresseddecoded version of said stored file as stored to said DEF or an original version of said stored file as stored to said DEF;
a second step of directing said statusoutcome of said first step of selecting so as to determine whether a step of said decompressing and decoding will output either a decompresseddecoded version of said stored file or an original version of said stored file;
verifying said either decompresseddecoded version of said stored file or an original version of said stored file;
detecting and extracting new fileprints from said stored file;
comparing said new fileprints to said retrieved fileprints of said stored file, wherein similarity measurements are made;
performing a storage-retrieval-registration-and verification-approver process on said similarity measurements; and
outputting said data file if appropriate similarity measurements have been made.
5. Method of claim 4, wherein said step of performing a storage-retrieval-registration-and verification-approver process further comprises the steps of detecting changes in, clarifying ownership of, and authenticating said stored file.
6. Method of claims 4 and 5, further comprising a step of ABC-processing each of said segments; wherein said ABC-processing further comprises the steps of:
first-stage filtering for averaging over frequency using a symmetric unity-gain filter employing a Harming window with 41 coefficients;
second-stage filtering for averaging over frequency using a symmetric unity-gain FIR filter employing a Hanning window with 11 coefficients and circular convolution;
thirty stage filtering;
setting the threshold of said first-stage filtering to the estimate of the average noise power of said segments; and
setting the threshold of said second-stage and said third-stage filtering to zero.
7. Method of claims 6, wherein said files are audio files.
8. Method of claim 7, further comprising the step of simulating unauthorized changes to a data file by setting all of the least significant bits of the 16-bit audio samples to \u201czero\u201d.
9. Method of claims 6, wherein said files are image files.
10. Method of claim 9, further comprising the step of simulating unauthorized changes to a data file by setting all of the least significant bits of the 8-bit RGB components to \u201czero\u201d.
11. Apparatus for detecting and extracting fileprints (DEF), comprising:
a secure key for generating DEF parameters to be utilized in subsequent DEF components;
selecting parameters for said secure key comprising an integer N, said integer N being both a fixed value and a power of 2;
a segment selector for partitioning a data sequence into segments using parsing parameters generated by said secure key;
a periodogram calculator for estimating the power spectral density of said segments, wherein each said segment comprises N-samples and an integer N being generated by said secure key;
an ABC processor for processing each of said segments using ABC parameters, said ABC parameters, including a number of stages M, being generated by said secure key so as to produce an ABC-processed segments;
a threshold-based detector for generating fileprints by threshold-detection-comparing said ABC-processed segments to thresholds from said secure key;
a compressorencoder for compressing and encoding said fileprints so as to reduce their size prior to outputting them and
means for extracting and outputting said compressed and encoded fileprints.
12. Apparatus as in claim 11, wherein said periodogram calculator further comprises means for performing a fast fourier transform (FFT).
13. Apparatus as in claim 11, wherein said means for selecting further comprises means for selecting parsing, ABC and threshold parameters.
14. Apparatus for storing files using a detector and extractor of fileprints (DEF), comprising:
a compressorencoder for compressing and encoding an input data file;
a first switch for selecting either said input data file or said compressed and encoded input data file to be sent to a router for storage;
means for sending said selected file to a router for storage;
a second switch for selecting fileprint extraction from either said input data file or said compressed and encoded input data file;
a first means for storing on a first storagesystem network, comprising:
storing a status of said first switch for selecting;
storing said fileprints;
storing DEF parameters, and
storing input data file identification; and
a second means for storing on a second storagesystem network, comprising:
storing said status of said second switch for selecting;
storing a version of said selected file from a router, and
storing input data file identification,
means for requesting a retrieval by identifying a stored file;
first means for retrieving from said first storagesystem network said stored file and said status of said first switch for selecting;
means for decompressing and decoding a retrieved said stored file;
a second means for retrieving from said second storagesystem network, comprising:
retrieving said status of said second switch for selecting;
retrieving said fileprints of said stored file, and
retrieving said DEF parameters associated with said stored file;
means for directing said DEF parameters to said DEF;
a first means for directing said status of said second switch for selecting so as to determine whether a step of said decompressing and decoding will output either a decompresseddecoded version of said stored file as stored to said DEF or an original version of said stored file as stored to said DEF;
a second means for directing said status of said first switch for selecting so as to determine whether a step of said decompressing and decoding will output either a decompresseddecoded version of said stored file or an original version of said stored file;
means for verifying either said decompresseddecoded version of said stored file or an original version of said stored file
means for detecting and extracting new fileprints from said stored file means for comparing said new fileprints to said retrieved fileprints of said stored file, wherein similarity measurements are made;
means for performing a storage-retrieval-registration-and verification-approver process on said similarity measurements; and
means for outputting said data file if appropriate similarity measurements have been made.
15. Apparatus as in claim 14, wherein said means for performing a storage-retrieval-registration-and verification-approver process further comprises means for detecting changes in, clarifying ownership of, and authenticating said stored file.
16. Apparatus as in claims 14 and 15, further comprising means for ABC-processing each of said segments, said means for ABC-processing further comprising:
a first-stage filter for averaging over frequency using a symmetric unity-gain filter employing a Hanning window with 41 coefficients; and
a second-stage filtering for averaging over frequency using a symmetric unity-gain FIR filter employing a Hanning window with 11 coefficients and circular convolution;
a third stage filter;
means for setting the threshold of said first-stage filter to the estimate of the average noise power said segments; and
means for setting the threshold of said second-stage and said third-stage filters to zero.
17. Apparatus as in claim 16, wherein said files are audio files.
18. Apparatus as in claim 17, further comprising means for simulating unauthorized changes to a data file, wherein all of the least significant bits of the 16-bit audio samples are set to \u201czero\u201d.
19. Apparatus as in claims 16, wherein said files are image files.
20. Apparatus as in claim 19, further comprising means for simulating unauthorized changes to a data file, wherein all of the least significant bits of the 8-bit RGB components are set to \u201czero\u201d.