1. A method of manufacturing a flash memory device, comprising the steps of:
providing a semiconductor substrate in which a device separation film is formed;
forming a tunnel oxide film and a first polysilicon layer on said semiconductor device;
subsequently patterning said tunnel oxide film and said first polysilicon layer to form a floating gate;
forming a mask to expose a portion in which a source region will be formed;
removing said device separation film at the exposed portion;
forming a dielectric film comprising a lower oxide film, a nitride film and an upper oxide film on the entire structure, performing an annealing process, and then forming a second polysilicon layer on said dielectric film;
sequentially removing said polysilicon layer, said upper oxide film, and said nitride film in a portion in which a source region and a drain region will be formed, and injecting impurity ions into said semiconductor substrate at a portion in which said lower oxide film remains to form a source region and a drain region;
after removing said remaining lower oxide film, sequentially forming a third polysilicon layer and a tungsten silicide layer on the entire structure and then patterning said third polysilicon layer and said tungsten silicide layer to form a control gate; and
performing an annealing process for activating the impurity ions injected into said source region and said drain region.
2. The method of claim 1, comprising the step of patterning said floating gate in X and Y directions so that the gate can have an independent shape.
3. The method of claim 1, comprising the step of removing said device separation film by a wet etching process using a HF solution of 50:1 concentration.
4. The method of claim 1, comprising the step of forming said dielectric film and said second polysilicon layer by a low pressure chemical vapor deposition method.
5. The method of claim 1, comprising the step of removing said upper oxide film and said nitride film by a plasma etching process.
6. The method of claim 1, wherein said remaining lower oxide film is amorphous.
7. The method of claim 1, comprising the step of injecting said impurity ions with an ion injection energy of about 30 KeV to about 100 KeV in an amount of about 5E15 ionscm2 to about 1E15 ionscm2.
8. The method of claim 1, wherein said impurity ions are selected from arsenide and phosphorous.
9. The method of claim 1, comprising the step of performing said annealing process by a rapid thermal process under nitrogen atmosphere.
10. The method of claim 9, comprising the step of performing said rapid thermal process for about 5 seconds to about 30 seconds, while continuously increasing the temperature up to about 900 C. to about 1000 C. at a rate of 50 C.sec.
The claims below are in addition to those above.
All refrences to claims which appear below refer to the numbering after this setence.
1-25. (canceled)
26. A dual energy x-ray absorptiometry (DEXA) method for determining visceral fat of a selected sub-volume of a visceral fat volume of a patient, which visceral fat volume is surrounded by a subcutaneous fat volume and together therewith forms a total volume of a length of the patient’s body, comprising:
acquiring x-ray measurements for respective pixel positions related to a two-dimensional projection image of said total volume, wherein at least some of the measurements are dual-energy x-ray measurements;
computer processing at least said x-ray measurements, including said dual-energy x-ray measurements, to provide an estimate of visceral fat of said sub-volume of the visceral fat volume; and
providing and displaying selected results related to said estimate of visceral fat of said sub-volume.
27. The method of claim 26 in which said visceral fat sub-volume is an individual organ of the patient that is within said visceral fat volume of the patient.
28. The method of claim 27 in which said organ is the patient’s liver that is within said visceral fat volume of the patent.
29. The method of claim 26 including determining a total area \u03b1t of a slice through said total volume, a subcutaneous fat area \u03b1s of a subcutaneous fat portion of said slice, and a visceral fat area \u03b1v of a visceral fat portion of said slice.
30. The method of claim 29 in which said computer processing further comprises using digital information describing said areas \u03b1t, \u03b1s and \u03b1v to calculate total fat Mt(Fat) of at least said slice and visceral fat Fatv of at least said slice.
31. The method of claim 29 in which said computer processing comprises calculating said visceral fat in said visceral fat volume of the patient as Fatv=(M1(Fat))\u2212\u03b1s wps), where Fatv is the fat in said visceral fat volume of the patient, w is a length estimate of said total volume, and ps is an estimate of density of fat.
32. The method of claim 29 in which said determining comprises computer processing said x-ray measurements to estimate at least some of said areas \u03b1t, \u03b1s and \u03b1v.
33. The method of claim 32 in which said determining comprises computer processing said x-ray measurements to estimate each of said areas \u03b1t, \u03b1s and \u03b1v.
34. The method of claim 32 in which said computer processing to estimate at least some of said areas \u03b1t, \u03b1s and \u03b1v comprises estimating (a) a major and a minor axis of an ellipse approximating the body slice, and (b) a portion of a major axis related to subcutaneous fat.
35. The method of claim 26 in which said acquiring comprises deriving at least some of said x-ray measurements from a lateral projection image of said total volume.
36. The method of claim 26 in which said computer processing further comprises using at least said x-ray measurements to determine an estimate of lean tissue and of visceral fat Fatv in at least a slice of said total volume, and using said estimates of lean tissue and of visceral fat Fatv to calculate a percentage metric for visceral fat of at least said slice.
37. A dual energy x-ray absorptiometry (DEXA) method for determining visceral fat of a visceral fat volume of a patient surrounded by a subcutaneous fat volume and forming therewith a total volume of a length of the patient’s body, comprising:
acquiring x-ray measurements for respective pixel positions related to a two-dimensional projection image of said total volume, wherein at least some of the measurements are dual-energy x-ray measurements;
determining a total area \u03b1t of a slice through said total volume, a subcutaneous fat area \u03b1s of a subcutaneous fat portion of said slice, and a visceral fat area \u03b1v of a visceral fat portion of said slice;
computer processing said x-ray measurements and digital information describing said areas \u03b1t, \u03b1s and \u03b1v to calculate a metric Fatv related to visceral fat in said visceral fat area \u03b1v; and
providing and displaying selected results related to said metric Fatv, said selected results pertaining to at least said slice of said total volume of a length of the patient.
38. The method of claim 37 in which said computer processing comprises using at least said x-ray measurements to calculate a metric Mt(Fat) related to total fat in said slice.
39. The method of claim 38 in which said computer processing comprises calculating said metric Fatv according to Fatv=(Mt Fat)\u2212\u03b1s wps), where w is a length estimate of said total volume and ps is an estimate of density of fat.
40. The method of claim 37 in which said determining comprises computer processing said x-ray measurements to estimate at least some of said areas \u03b1t, \u03b1s and \u03b1v.
41. The method of claim 40 in which said determining comprises computer processing said x-ray measurements to estimate each of said areas \u03b1t, \u03b1s and \u03b1v.
42. The method of claim 40 in which said computer processing to determine at least some of said areas \u03b1t, \u03b1s and \u03b1v comprises estimating (a) a major and a minor axis of an ellipse approximating the body slice, and (b) a portion of a major axis related to subcutaneous fat.
43. The method of claim 37 comprising deriving at east some of said x-ray measurements from a lateral projection image of said total volume.
44. The method of claim 37 in which said computer processing further comprises using at least said the x-ray measurements to calculate a metric related to lean tissue in said slice.
45. The method of claim 44 in which said computer processing further comprises using said metric related to lean tissue and said metric Fatv to calculate a percentage metric for visceral fat of at least said slice.
46. The method of claim 37 in which said computer processing comprises calculating a metric for leftright symmetry of said metric Fatv relative to the patient’s body.
47. The method of claim 37 including displaying the metric Fatv of the patient in combination with ranges of metrics for a population of other patients matched to the patient by one or more selected characteristics including at least one of age and sex.
48. The method of claim 37 in which said computer processing comprises calculating individual estimates of visceral fat for each of a number of the pixel positions.
49. A method as in claim 37 in which said computer processing includes calculating individual estimate of subcutaneous fat for each of a number of said pixel positions.
50. A dual energy x-ray absorptiometry (DEXA) system for determining visceral fat of a visceral fat volume of a patient surrounded by a subcutaneous fat volume to form therewith a total volume of a length of the patient’s body, comprising:
an x-ray data acquisition unit acquiring x-ray measurements for respective pixel positions related to a two-dimensional projection image of said total volume of a length of the patient’s body, wherein at least some of the measurements are dual-energy x-ray measurements;
a source of digital information describing a total area \u03b1t of a slice through said total volume, a subcutaneous fat area \u03b1s of a subcutaneous fat portion of said slice, and a visceral fat area \u03b1v of a visceral fat portion of said slice;
a programmed digital computer configured to process said said x-ray measurements as well as digital information describing said total area \u03b1t of said slice, subcutaneous fat area \u03b1s, and visceral fat area \u03b1v and thereby calculate a metric Fatv related to visceral fat said visceral fat area \u03b1v; and
a display unit providing and displaying selected results related to said metric Fatv, said selected results pertaining to at least said slice of said total volume of a length of the patient.
51. The system of claim 50 in which said computer is further configured to process at least said x-ray measurements to calculate a metric Mt(Fat) related to total fat in said slice.
52. The system of claim 51 in which said computer is further configured to calculate said metric Fatv according to Fatv=(Mt Fat)\u2212\u03b1s wps), where w is a length estimate of said total volume and ps is an estimate of density of fat.
53. The system of claim 50 in which said source of digital information is said computer, which is further configured to generate said digital data describing at least some of said areas \u03b1t, \u03b1s and \u03b1v by processing said x-ray measurement.
54. The system of claim 53 in which said computer is configured to generate said digital data describing each of said areas \u03b1t, \u03b1s and \u03b1v by processing said x-ray measurement.
55. The method of claim 54 in which said processing to determine said areas \u03b1t, \u03b1s and \u03b1v comprises estimating (a) a major and a minor axis of an ellipse approximating the body slice, and (b) a portion of a major axis related to subcutaneous fat.
56. The system of claim 50 in which said x-ray data acquisition unit acquires said x-ray measurements from a lateral view of he patient.
57. The system of claim 50 in which said computer is further configured to calculate a metric related to lean tissue in said slice using at least said x-ray measurements.
58. The system of claim 57 in which said computer is further configured to process said metric related to lean tissue and the metric Fatv to calculate a percentage metric for visceral fat of at least said slice.
59. The system of claim 50 in which said computer is further configured to calculate a metric for leftright symmetry of said metric Fatv relative to the patient’s body.
60. The system of claim 50 in which said computer is further configured to provide information regarding the metric Fatv of the patient in combination with ranges of metrics for a population of other patients matched to the patient by one or more selected characteristics including at least one of age and sex, and said display is configured to display said information.
61. A dual energy x-ray absorptiometry (DEXA) method for determining visceral fat in a visceral fat volume of a patient surrounded by a subcutaneous fat volume and forming therewith a total volume of a length of the patient’s body, comprising:
acquiring x-ray measurements for respective pixel positions related to a two-dimensional projection image of said total volume, wherein at least some of the measurements are dual-energy x-ray measurements;
computer-processing said x-ray measurements to identify a size measure of said subcutaneous fact volume;
further computer-processing said x-ray measurements to identify a size measure of said visceral fat volume; and
still further computer-processing said x-ray measurements and said size measure of the visceral fat volume to calculate a metric of visceral fat contained in said visceral fat volume; and
providing and displaying selected results related to said metric of visceral fat contained in said total volume of a length of the patient.
62. A dual energy x-ray absorptiometry (DEXA) system for determining visceral fat in a visceral fat volume of a patient surrounded by a subcutaneous fat volume and forming therewith a total volume of a length of the patient’s body, comprising:
a data acquisition unit acquiring x-ray measurements for respective pixel positions related to a two-dimensional projection image of said total volume, wherein at least some of the measurements are dual-energy x-ray measurements;
a processing unit computer-processing said x-ray measurements to identify a size measure of said subcutaneous fact volume, a size measure of said visceral fat volume, and further computer-processing said x-ray measurements and said size measure of the visceral fat volume to calculate a metric of visceral fat contained in said visceral fat volume; and
a display unit providing and displaying selected results related to said metric of visceral fat contained in said total volume of a length of the patient.