1. An apparatus for one trip drilling and completion of a well, comprising:
a tubular having at least one opening and an extendable sand control device associated with said opening, said sand control device comprising an outwardly extending tubular element selectively extendable relative to said opening where it is mounted;
a drilling apparatus further comprising a drill string supporting at least one bit, said drilling apparatus rotating and advancing said tubular as said bit drills the well; and
a temporary blocking medium for said sand control device said blocking medium being adapted to initially block fluid flow through said sand control device as said sand control device is extended and said tubular is externally sealed in the well with a sealing material delivered through it and to subsequently allow fluid flow through said extended sand control device and said now externally sealed tubular after said sealing material has set up.
2. The apparatus recited in claim 1, further comprising:
an apparatus adapted to pump a sealing material through said tubular to seal said tubular in place in a well bore.
3. The apparatus recited in claim 2, wherein said sealing material is cement.
4. The apparatus recited in claim 2, wherein said tubular is mounted to a rotatable drill string.
5. The apparatus recited in claim 4, wherein:
said sealing apparatus is incorporated within said drill string; and
said drilling apparatus comprises a drilling tool mounted to a lower end of said tubular.
6. The apparatus recited in claim 2, wherein:
said tubular is mounted to a production string; and
said drilling apparatus comprises a drilling tool driven by a downhole motor.
7. The apparatus recited in claim 6, wherein:
said drilling tool is adapted to pass through, and extend below, said tubular; and
said sealing apparatus is adapted to pass through said production string after removal of said drilling apparatus.
8. The apparatus recited in claim 1, wherein:
said sand control device comprises a gravel pack material.
9. The apparatus recited in claim 1, wherein:
said temporary blocking medium comprises a wax material, said wax material being removable by application of an agent selected from the following: an acid, a hydrocarbon, or heat.
10. The apparatus recited in claim 1, wherein:
said temporary blocking medium comprises a polymer material, said polymer material being removable by biodegradation.
11. The apparatus recited in claim 1, wherein:
said temporary blocking medium comprises a frangible disk.
12. A method for one trip drilling and completion of a well, comprising:
providing a tubular with an extendable sand control medium and a temporary blocking medium for at least one opening thereon;
providing a drilling apparatus discrete from said tubular that supports said tubular;
drilling a well bore with a bit on said drilling apparatus while selectively advancing said tubular with said drilling apparatus;
extending said sand control medium;
cementing said tubular when said drilling places it in a desired position and said sand control medium is extended;
partially or totally disabling said blocking medium after said cementing; and
passing fluid through said opening.
13. The method recited in claim 12, further comprising:
initially blocking fluid flow through said opening with said blocking medium; and
removing said blocking medium to subsequently allow fluid flow through said opening.
14. The method recited in claim 12, wherein:
mounting said tubular to a rotatable drill string which further comprises a drilling tool mounted to a lower end of said tubular; and
rotating said tubular and said drilling tool with said drill string.
15. The method recited in claim 12, wherein:
mounting said tubular to a production string and
providing as said drilling apparatus a drilling tool driven by a downhole motor.
16. The method recited in claim 15, wherein:
passing said drilling tool through said tubular; and
rotating said drilling tool with said downhole motor.
17. The method recited in claim 16, further comprising:
removing said drilling apparatus from said production string after said drilling;
providing a cementing apparatus;
pumping cement through said tubular with said cementing apparatus to cement said tubular in place in the well bore;
lowering said cementing apparatus through said production string prior to pumping said cement.
18. The method recited in claim 12, wherein:
providing as said temporary blocking medium a wax material; and
removing said blocking medium by dissolving said wax material or by application of an acid, a hydrocarbon, or heat.
19. The method recited in claim 12, wherein:
providing as said temporary blocking medium a polymer material; and removing said blocking medium by biodegradation of said polymer material.
20. The method recited in claim 12, wherein:
providing as said temporary blocking medium a frangible disk; and
removing said blocking medium by rupturing of said frangible disk.
21. The method of claim 12, comprising:
providing an outwardly telescoping tubular element associated with each said opening;
and disposing said sand control medium and said temporary blocking medium in a passage of said telescoping tubular element.
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 for fabricating an NROM semiconductor memory device, said method having the steps of:
(a) providing a plurality of u-shaped MOSFETs\u2014which are spaced apart from one another and have a multilayer dielectric, in particular an ONO or Al2O3 dielectric, which is suitable for charge trapping\u2014along rows in a first direction and along columns in a second direction in trenches a semiconductor substrate;
(b) providing sourcedrain regions between the u-shaped MOSFETs in interspaces between the rows which run parallel to the columns;
(c) providing isolation trenches in the sourcedrain regions between the u-shaped MOSFETs of adjacent columns as far as a particular depth in the semiconductor substrate, said isolation trenches cutting the sourcedrain regions into respective bit lines;
(d) filling the isolation trenches with an insulation material; and
(e) providing word lines for connecting respective rows of u-shaped MOSFETs.
2. The method as claimed in claim 1, wherein the following steps are carried out:
(a) using a hard mask to form the trenches as longitudinal trenches corresponding to respective columns of of u-shaped MOSFETs;
(b) forming the multilayer dielectric on the trench walls;
(c) filling the trenches partially with a gate electrode material;
(d) closing the trenches with an insulation cover which is flush with the surface of the hard mask;
(e) removing the insulation cover, the gate electrode material and the multilayer dielectric from the trench walls and isolation regions are formed in order to separate the individual u-shaped MOSFETs along the columns.
3. The method as claimed in claim 2, wherein the following steps are carried out:
(a) forming openings in the hard mask in the interspaces in order to expose the semiconductor substrate, sidewall spacers remaining as a mask above the semiconductor substrate next to the trenches;
(b) implanting ions through the openings and subsequent diffusion is carried out in order to form the sourcedrain regions;
(c) etching the isolation trenches through the openings.
4. The method as claimed in claim 1, wherein the bit lines of adjacent MOSFETs are electrically connected in pairs by providing conductive straps in the isolation trenches.
5. The method as claimed in claim 1, wherein the trenches are rounded in the lower trench region before the multilayer dielectric is formed on the trench walls.
6. The method as claimed in claim 1, wherein the trenches are configured in an angular manner in the lower trench region, and, before the multilayer dielectric is formed on the trench walls, ions are implanted into the trenches using the hard mask and subsequent implantation is carried out in order to form channel blocking regions in the semiconductor substrate under the trenches.
7. An NROM semiconductor memory device having:
(a) a plurality of u-shaped MOSFETs\u2014which are spaced apart from one another and have a multilayer dielectric, in particular an ONO dielectric, which is suitable for charge trapping\u2014along rows in a first direction and along columns in a second direction in trenches in a semiconductor substrate;
(b) sourcedrain regions between the u-shaped MOSFETs in interspaces between the rows which run parallel to the columns;
(c) isolation trenches in the sourcedrain regions between the u-shaped MOSFETs of adjacent columns as far as a particular depth in the semiconductor substrate, said isolation trenches cutting the sourcedrain regions into respective bit lines and being filled with an insulation material; and
(d) word lines for connecting respective rows of u-shaped MOSFETs.
8. The device as claimed in claim 7, wherein the bit lines of adjacent MOSFETs are electrically connected in pairs by means of conductive straps in the isolation trenches.
9. The device as claimed in claim 7, wherein the trenches are rounded in the lower trench region.
10. The device as claimed in claim 7, wherein the trenches are configured in an angular manner in the lower trench region, and channel blocking regions are provided in the semiconductor substrate under the trenches.