1. A method of providing a watercraft with improved ice penetration characteristics, which watercraft has a hull with a first end and a second end and which is equipped at said second end with a propulsion arrangement which provides both the main propulsive thrust of the watercraft while the watercraft moves with either end ahead and the steering of the watercraft, wherein said second end of the hull is shaped and designed so that it has efficient ice penetration characteristics in that the watercraft has a design waterline and the second end of the hull is oblique in the vicinity of the design waterline and somewhat above it, said propulsion arrangement includes at least three propulsion devices each provided with a propeller, at least a majority of the propulsion devices are rudder propeller devices, and the propeller of at least one of the propulsion devices is at a first distance from the second end of the hull and the propeller of at least another one of the propulsion devices is at a second distance, greater than the first distance, from the second end of the hull, so that that when the watercraft moves in ice or ice build-ups with said second end ahead, at least one propeller at said first distance from said second end of the hull breaks ice and at least one propeller at said second distance from said second end of the hull moves disintegrated ice or ice chunks away from the ice build-up.
2. A method according to claim 1, comprising using at least one of the propulsion devices to blow a water stream towards an ice build-up for breaking the ice build-up.
3. A watercraft with improved ice penetration characteristics, which watercraft has a hull with a first end and a second end and which is equipped at said second end with a propulsion arrangement that provides both the main propulsive thrust of the watercraft while the watercraft moves with either end ahead and the steering of the watercraft, wherein said second end of the hull is shaped and designed so that it has efficient ice penetration characteristics in that the watercraft has a design waterline and the second end of the hull is oblique in the vicinity of the design waterline and somewhat above it, said propulsion arrangement includes at least three propulsion devices each provided with a propeller, at least a majority of the propulsion devices are rudder propeller devices, and the propeller of at least one of the propulsion devices is at a first distance from the second end of the hull and the propeller of at least another one of the propulsion devices is at a second distance, greater than the first distance, from the second end of the hull, so that when the watercraft moves in ice or ice build-ups with said second end ahead, at least one propeller at said first distance from said second end of the hull breaks ice and at least one propeller at said second distance from said second end of the hull moves disintegrated ice or ice chunks away from the ice build-up.
4. A watercraft according to claim 3, wherein the propellers of at least two of the propulsion devices are at said first distance from the second end of the hull.
5. A watercraft according to claim 4, wherein the at least two propulsion devices with a propeller at said first distance from the second end of the hull are rudder propeller devices.
6. A watercraft according to claim 3, wherein two of the propulsion devices are rudder propeller devices each having a propeller at said first distance from the second end of the hull, the two rudder propeller devices being spaced from a longitudinal center line of the hull and at opposite respective sides of the longitudinal center line, and wherein a shaft driven propulsion device having a propeller at said second distance from the second end of the hull is disposed between the rudder propeller devices.
7. A watercraft according to claim 6, wherein the rudder propeller devices in all provide at least a half of the total propulsion power of the watercraft.
8. A method of operating a watercraft, wherein the watercraft has a hull with a first end and a second end and which is equipped at said second end with a propulsion arrangement which provides both the main propulsive thrust of the watercraft while the watercraft moves with either end ahead and the steering of the watercraft, wherein the watercraft has a design waterline and the second end of the hull is oblique in the vicinity of the design waterline and somewhat above it, wherein said propulsion arrangement includes at least three propulsion devices each provided with a propeller, at least a majority of the propulsion devices are rudder propeller devices, and the propeller of at least one of the propulsion devices is at a first distance from the second end of the hull and the propeller of at least another one of the propulsion devices is at a second distance, greater than the first distance, from the second end of the hull, said method comprising operating the watercraft in ice conditions with said second end ahead, so that at least one propeller at said first distance from said second end of the hull breaks ice and at least one propeller at said second distance from said second end of the hull moves disintegrated ice or ice chunks away from the ice build-up.
9. A method according to claim 8, wherein two of the propulsion devices are rudder propeller devices each having a propeller at said first distance from the second end of the hull, the two rudder propeller devices being spaced from a longitudinal center line of the hull and at opposite respective sides of the longitudinal center line, and wherein the method comprises positioning the two rudder propeller devices so the propellers of the two rudder propeller devices bore into the ice as the watercraft moves against the ice.
10. A method according to claim 8, comprising using at least one of the propulsion devices to blow a water stream towards an ice build-up for breaking the ice build-up.
11. A method according to claim 8, wherein the propellers of at least two of the propulsion devices are at said first distance from the second end of the hull.
12. A method according to claim 11, wherein the at least two propulsion devices whose propellers are at said first distance from the second end of the hull are rudder propeller devices.
13. A method according to claim 8, wherein two of the propulsion devices are rudder propeller devices each having a propeller at said first distance from the second end of the hull, the two rudder propeller devices being spaced from a longitudinal center line of the hull and at opposite respective sides of the longitudinal center line, and wherein a shaft driven propulsion device having a propeller at said second distance from the second end of the hull is disposed between the rudder propeller devices.
14. A method according to claim 13, wherein the rudder propeller devices in all provide at least a half of the total propulsion power of the watercraft.
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. A method of manufacturing a semiconductor device, comprising:
forming a first pattern in a first region over a semiconductor substrate;
forming a second pattern in a second region separated from the first region over the semiconductor substrate;
depositing an interlayer insulation film to cover the first and second patterns;
forming a photoresist film on the interlayer insulation film;
treating the photoresist film in stepper exposure and development to form a photoresist pattern of a photomask having its device pattern matched with the first pattern and its alignment marks matched with the second pattern;
selectively etching off the interlayer insulation film over the first and second patterns, with the photoresist pattern; and
after removing the photoresist pattern, flattening the interlayer insulation film to expose the surfaces of the first and second patterns, respectively.
2. A method according to claim 1, wherein the flattening the interlayer insulation film is performed by chemical mechanical polishing the interlayer insulation film.
3. A method according to claim 1, wherein the photomask is provided with marks for forming inspection targets for misalignment, and the step of forming a second pattern includes, prior to the depositing an interlayer insulation film, forming the second pattern that matches with the marks for forming inspection targets for misalignment.
4. A method according to claim 1, further comprising: after flattening the interlayer insulation film, removing the first pattern to form trenches, and filling the trenches with a material to create a third pattern.
5. A method according to claim 4, wherein the forming a third embedded pattern includes defining transistor gate electrodes in that pattern.
6. A method according to claim 5, further comprising:
prior to depositing an interlayer insulation film, implanting impurities in the semiconductor substrate to form transistor source and drain regions, with a mask of the first pattern.
7. A method according to claim 4, wherein the removing the first pattern includes simultaneously removing the second pattern to form trenches, and thereafter filling the trenches with the identical material to that for the third pattern.
8. A method according to claim 1, wherein the first and second patterns are simultaneously formed in a single forming using the same material.
9. A method according to claim 1, wherein the photoresist pattern over the second pattern is shaped in an almost cross-like plane pattern.
10. A method of manufacturing a semiconductor device, comprising:
forming dummy gate electrodes in a device formation area of a semiconductor device, and forming a dishing inhibiting pattern in a target area of the semiconductor device;
forming an interlayer insulation film to cover the dummy gate electrodes and the dishing inhibiting pattern;
after covering the interlayer insulation film with a photoresist film, treating the photoresist film in stepper exposure and development to form a photoresist pattern of a photomask having its device pattern matched with the dummy gate electrodes and its alignment marks matched with the dishing inhibiting pattern or having its marks for forming inspection targets for misalignment matched with the same;
selectively etching the interlayer insulation film over the dummy gate electrodes and the dishing inhibiting pattern, with the photoresist pattern;
after removing the photoresist pattern, flattening the interlayer insulation film by means of chemical mechanical polishing to expose the surfaces of the dummy gate electrodes and the dishing inhibiting pattern, respectively; and
removing the dummy gate electrodes and filling with a material to form gate electrodes.
11. A method of manufacturing a semiconductor device, comprising:
forming dummy gate electrodes in a device formation area of a semiconductor device, and forming a dishing inhibiting pattern in a target area of the semiconductor device;
forming a nitride film to cover the dummy gate electrodes and the dishing inhibiting pattern, thereby setting side walls of the nitride film on opposite sides of each of the dummy gate electrodes;
covering the entire surface of the semiconductor substrate with an interlayer insulation film;
after covering the interlayer insulation film with a photoresist film, treating the photoresist film in stepper exposure and development to form a photoresist pattern of a photomask having its device pattern matched with the dummy gate electrodes and its alignment marks matched with the dishing inhibiting pattern or having its marks for forming inspection targets for misalignment matched with the same;
selectively etching the interlayer insulation film over the dummy gate electrodes and the dishing inhibiting pattern, with the photoresist pattern;
after removing the photoresist pattern, treating the interlayer insulation film and the nitride film in chemical mechanical polishing to expose the surfaces of the dummy gate electrodes and the dishing inhibiting pattern, respectively; and
removing the dummy gate electrodes and filling with a material to form gate electrodes.
12. A method of manufacturing a semiconductor device, comprising:
forming dummy gate electrodes in a device formation area of a semiconductor device, and forming a dishing inhibiting pattern in a target area of the semiconductor device;
selectively etching the dishing inhibiting pattern to form pattern trenches;
depositing an interlayer insulation film to cover the dummy gate electrodes and the dishing inhibiting pattern and filling the pattern trenches with the interlayer insulation film to create targets in the dishing inhibiting pattern for alignment with a photomask;
after covering the interlayer insulation film with a photoresist film, treating the photoresist film in stepper exposure and development to form a photoresist pattern of the photomask having its device pattern matched with the dummy gate electrodes and its alignment marks matched with the targets in the dishing inhibiting pattern or having its marks for forming inspection targets for misalignment matched with the same;
selectively etching the interlayer insulation film over the dummy gate electrodes and the dishing inhibiting pattern, with the photoresist pattern;
after removing the photoresist pattern, flattening the interlayer insulation film by means of chemical mechanical polishing to expose the surfaces of the dummy gate electrodes and the dishing inhibiting pattern, respectively; and
removing the dummy gate electrodes to obtain gate trenches and filling the gate trenches with material of electrode to form gate electrodes.
13. A semiconductor device having a first region provided with semiconductor devices and a second region provided with targets for alignment with a photomask, comprising:
a first pattern formed in the first region,
a second pattern formed in the second region,
an interlayer insulation film surrounding the first and second patterns and having its surface flattened, and
alignment targets around the second pattern within lamination of the semiconductor substrate.
14. A semiconductor device according to claim 13, wherein the first pattern is an interconnection.