1. A semiconductor device with improved leakage control, comprising:
a P doped semiconductor substrate having a top surface;
a STI in said substrate, said STI having a bottom, a first sidewall and an opposite second sidewall;
a P-type leakage stop implant in said substrate under the bottom of said STI, all of said P-type leakage stop implant aligned between said second sidewall and an axis equally spaced between said first and second sidewalls; and
an N-well in said substrate adjacent to and in contact with said first sidewall, said N-well extending under said STI and forming an upper side portion of an isolation junction with said leakage stop implant and forming a bottom and a lower side portion of said junction with dopant species in said substrate, said upper portion of said isolation junction located entirely under said STI.
2. The semiconductor device of claim 1, further comprising a P-well in said substrate adjacent to and in contact with said second sidewall, said P-well incorporated into said isolation junction.
3. The semiconductor device of claim 2, wherein said STI is 0.05 to 1 micron in depth and 0.1 to 5 microns in width.
4. The semiconductor device of claim 2, further comprising a PFET in said N-well and an NFET in said P-well.
5. The semiconductor device of claim 1, wherein said leakage stop implant extends under said STI from said second sidewall toward said first sidewall a distance equal to 10 to 40% of the width of said STI.
6. The semiconductor device of claim 1, wherein the concentration of P dopant at an interface formed by the bottom of said STI and said substrate is 3E16 atmcm3 to 1E17 atmcm3.
7. The semiconductor device of claim 6, wherein the concentration of P dopant at about 0.1 micron below said interface under said second sidewall is 1.0E17 atmcm3 to 1.5E17 atmcm3.
8. The semiconductor device of claim 1, further comprising spacers on said first and second sidewalls of and contained within said STI.
9. The semiconductor device of claim 1, wherein said STI is filled with TEOS or HDP oxide.
10. The semiconductor device of claim 9, further including a liner on said bottom, said first sidewall and said second sidewall of said STI.
11. The semiconductor device of claim 10, wherein said liner is 10 to 30 nm thick thermal oxide.
12. The semiconductor device of claim 10, further comprising spacers on said liner over said first and second sidewalls of and contained within said STI.
13. The semiconductor device of claim 1, wherein:
said isolation junction contacts said bottom of said STI a first distance from said second sidewall of said isolation junction;
said isolation junction extends from said second sidewall a second distance at a first depth below said bottom of said STI;
said isolation junction extends from said second sidewall a third distance at a second depth below said bottom of said STI;
said isolation junction extends from said second sidewall a fourth distance at a third depth below said bottom of said STI;
said first depth less than said second depth, said second depth less than said third depth; and
said first and third distances greater than said second distance and first, second and third distances greater than said fourth distance.
14. A semiconductor device with improved leakage control, comprising:
an N doped semiconductor substrate having a top surface;
a STI in said substrate, said STI having a bottom, a first sidewall and an opposite second sidewall;
an N-type leakage stop implant in said substrate under the bottom of said STI, all of said N-type leakage stop implant aligned between said second sidewall and an axis equally spaced between said first and second sidewalls; and
a P-well in said substrate adjacent to and in contact with said first sidewall, said P-well extending under said STI and forming an upper side portion of an isolation junction with said leakage stop implant and forming a bottom and a lower side portion of said junction with dopant species in said substrate, said upper portion of said isolation junction located entirely under said STI.
15. The semiconductor device of claim 14, further comprising an N-well in said substrate adjacent to and in contact with said second sidewall, said N-well incorporated into said isolation junction.
16. The semiconductor device of claim 15, wherein said STI is 0.05 to 1 micron in depth and 0.1 to 5 microns in width.
17. The semiconductor device of claim 15, further comprising a NFET in said P-well and a PFET in said N-well.
18. The semiconductor device of claim 14, wherein said leakage stop implant extends under said STI from said second sidewall toward said first sidewall a distance equal to 10 to 40% of the width of said STI.
19. The semiconductor device of claim 14, wherein the concentration of N dopant at an interface formed by the bottom of said STI and said substrate is 3E16 atmcm3 to1E17 atmcm3.
20. The semiconductor device of claim 19, wherein the concentration of N dopant at about 0.1 micron below said interface under said second sidewall is 1.0E17 atmcm3 to 1.5E17 atmcm3.
21. The semiconductor device of claim 14, further comprising spacers on said first and second sidewalls of and contained within said STI.
22. The semiconductor device of claim 14, wherein said STI is filled with TEOS or HDP oxide.
23. The semiconductor device of claim 22, further including a liner on said bottom, said first sidewall and said second sidewall of said STI.
24. The semiconductor device of claim 23, wherein said liner is 10 to 30 nm thick thermal oxide.
25. The semiconductor device of claim 23, further comprising spacers on said liner over said first and second sidewalls of and contained within said STI.
26. The semiconductor device of claim 14, wherein:
said isolation junction contacts said bottom of said STI a first from said second sidewall or said isolation junction;
said isolation junction extends from said second sidewall a second distance at a first depth below said bottom of said STI;
said isolation junction extends from said second sidewall a third distance at a second depth below said bottom of said STI;
said isolation junction extends form said second sidewall a fourth distance at a third depth below said bottom or said STI;
said first depth loss than said second depth, said second depth loss than said third depth; and
said first and third distances greater than, said second distance and first, second and third distances greater than said fourth distance.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method for locating, in three-dimensional space and in relation to a predetermined location, an object emitting acoustic signals comprising the steps of:
deploying an array of acoustic transducers;
receiving acoustic signals at said deployed array including the acoustic signals from the object;
estimating a bearing from the predetermined location to the object in response to the received acoustic signals, said estimating including inverse beamforming processing the signals from each transducer in said deployed array using different frequencies and multipath analysis of said received acoustic signals;
repeatedly generating beam values for acoustic signals received by said deployed array from different incremental locations at incremental ranges and depths along the estimated bearing whereby bearing, depth and range information are provided as a function of time and a correlation value is obtained for each acoustic frequency and for each incremental location;
selecting an individual incremental location with a peak beam value based upon an inverse beamformer twenty-six nearest neighbor peak picker analysis comprising the steps of;
determining the center frequency of the received frequencies;
segmenting the received frequencies into n frequency bins greater than and less than the determined center frequency;
calculating the left half bandwidth of the peak beam values received for frequency bins less than the center frequency until the left half bandwidth BWLn becomes zero or negative;
calculating the right half bandwidth of the peak values received for frequency bins greater than the center frequencies until the right hand bandwidth BWRn becomes zero or negative;
adding the calculated left half bandwidth BWLn to the calculated right half bandwidth BWRn to obtain the total bandwidth, BW, said total bandwidth defining said selected individual incremental location; and
providing bearing, range and depth information from the predetermined location to the selected incremental location thereby locating the object in three-dimensional space.
2. The method according to claim 1 wherein:
said step of calculating the left half bandwidth utilizes the formula:
3
BW
L
n
=
BL
(
f
n
)
–
BL
(
f
n
–
1
)
f
n
–
f
n
–
1
;
and
said step of calculating the right hand bandwidth utilizes the formula:
4
BW
R
n
=
BL
(
f
n
+
1
)
–
BL
(
f
n
)
f
n
+
1
–
f
n
wherein
fn represents the center frequency of the n th frequency bin; and
BL represents the beam level.
3. An apparatus for locating, in three-dimensional space and in relation to a predetermined location, an object emitting acoustic signals comprising:
receiver means having a towed horizontal array of transducers for obtaining acoustic signals including the acoustic signals from the object, said acoustic signals having a plurality of frequencies;
an estimating means connected to said receiver means and responsive to the obtained acoustic signals for estimating the bearing to the object;
a beam value generating means joined to said estimating means for generating beam values for the obtained acoustic signals from different incremental locations at incremental ranges and depths along the estimated bearing;
a location selection means joined to said estimating means and said beam value generating means, said location selection means further including:
means for determining the center frequency of the obtained acoustic signals joined to receive the obtained acoustic signals;
means for segmenting the obtained acoustic signals into a plurality of frequency bins, n, said plurality of bins comprising right half bins having frequencies greater than the center frequency and left half bins having frequencies less than the center frequency, said means for segmenting being joined to said means for determining;
left half bandwidth calculation means joined to said means for segmenting and calculating the bandwidth of the peak beam values in the left half bins of segmented acoustic signals until the left half bandwidth BWLn becomes no less than zero;
right half bandwidth calculation means joined to said means for segmenting and calculating the bandwidth of the peak beam values in the right half bins of segmented acoustic signals until the right half bandwidth BWLn becomes no less than zero;
adding means joined to said left half calculation means and said right half calculation means for determining the total bandwidth, BW, as being equal to the sum of the left half bandwidth peak values added to the sum of the right half bandwidth peak values which defines a selected incremental location;
a calculating means is joined to said location selection means for calculating the bearing, range and depth from the predetermined location to the selected incremental location thereby locating the object in three-dimensional space; and
a display means for displaying the calculated bearing, range and depth joined to said calculating means.
4. The apparatus according to claim 3 wherein:
said left half bandwidth calculation means utilizes the formula:
5
BW
L
n
=
BL
(
f
n
)
–
BL
(
f
n
–
1
)
f
n
–
f
n
–
1
;
and
said right half bandwidth calculation means utilizes the formula:
6
BW
R
n
=
BL
(
f
n
+
1
)
–
BL
(
f
n
)
f
n
+
1
–
f
n
wherein:
fn represents the center frequency of the n th frequency bin; and
BL represents the beam level.