HIGH ASPECT RATIO GATES
Embodiments are directed to a method of forming a feature of a semiconductor device. In one or more embodiments, the feature is a gate, and the method includes forming a substrate and forming a gate material extending over a major surface of the substrate. The method further includes forming a trench extending through the gate material and into the substrate in a first direction, wherein the trench further extends through the gate material and the substrate in a second direction. The method further includes filling the trench with a fill material and forming individual gates from the gate material, wherein the individual gates extend along a third direction.
1 . A semiconductor structure comprising:
a substrate;
a first gate stack formed over the substrate;
a second gate stack formed over the substrate;
a first trench extending completely through the first gate stack and into but not completely through the substrate;
a second trench extending completely through the first gate stack and into but not completely through the substrate;
a third trench extending completely through the second gate stack and into but not completely through the substrate;
a fourth trench extending completely through the second gate stack and into but not completely through the substrate;
a first anchor formed in the first trench and the third trench; and
a second anchor formed in the second trench and the fourth trench.
2 . The structure of claim 1 , wherein the first anchor is physically coupled to the first gate stack and the second gate stack through sidewall portions of the first trench and sidewall portions of the third trench.
3 . The structure of claim 2 , wherein the second anchor is physically coupled to the first gate stack and the second gate stack through sidewall portions of the second trench and sidewall portions of the fourth trench.
4 . The structure of claim 3 , wherein:
the first trench extends into the substrate in a first direction and a second direction, wherein the first direction is substantially perpendicular to the second direction;
a top portion of the first anchor extends above a major surface of the substrate; and
the first trench further extends through the substrate and gate material of the first gate stack in a third direction;
5 . The structure of claim 4 , wherein each of the first and second gate stacks comprises:
a first sidewall having a first height (H) dimension extending along the first direction and a first length (L) extending along the third direction;
a second sidewall formed from a portion of the at least one inner trench sidewall and having a thickness (T) dimension extending along the second direction and a second H dimension extending along the first direction; and
a third sidewall having a third H dimension extending along the first direction and a second L dimension extending along the third direction;
wherein T is less than H;
wherein each of the individual gate structures is physically coupled to the top portion of the first anchor.
6 . The structure of claim 5 further comprising the second trench extending into the substrate in the first direction and the second direction.
7 . The structure of claim 6 further comprising a top portion of the second anchor extending above the major surface of the substrate.
8 . The structure of claim 7 , wherein each of the individual gate structures is physically coupled to the top portion of the second anchor.
9 . The structure of claim 8 , wherein a distance from the first trench to the second trench in the third direction matches a selected length dimension of each of the individual gate structures.
10 . The structure of claim 9 , wherein:
the length dimension extends along the third direction;
each of the individual gate structures further comprises a width dimension extending along the second direction;
the height dimension is greater than the width dimension; and
the first anchor and the second anchor prevent each of the individual gate structures from bending along the height dimension of each individual gate structure.
11 . A semiconductor structure comprising:
a substrate;
a first gate stack formed over the substrate;
a second gate stack formed over the substrate;
a first trench extending completely through the first gate stack and into but not completely through the substrate;
a second trench extending completely through the first gate stack and into but not completely through the substrate;
a third trench extending completely through the second gate stack and into but not completely through the substrate;
a fourth trench extending completely through the second gate stack and into but not completely through the substrate;
a first anchor formed in the first trench and the third trench; and
a second anchor formed in the second trench and the fourth trench;
wherein the first anchor and the second anchor prevent the first gate stack and the second gate stack from bending along a height dimension of the first gate stack or a height dimension of the second gate stack.
12 . The structure of claim 11 , wherein the first anchor is physically coupled to the first gate stack and the second gate stack through sidewall portions of the first trench and sidewall portions of the third trench.
13 . The structure of claim 12 , wherein the second anchor is physically coupled to the first gate stack and the second gate stack through sidewall portions of the second trench and sidewall portions of the fourth trench.
14 . The structure of claim 13 , wherein:
the first trench extends into the substrate in a first direction and a second direction, wherein the first direction is substantially perpendicular to the second direction;
a top portion of the first anchor extends above a major surface of the substrate; and
the first trench further extends through the substrate and gate material of the first gate stack in a third direction.
15 . The structure of claim 14 , wherein each of the first and second gate stacks comprises:
a first sidewall having a first height (H) dimension extending along the first direction and a first length (L) extending along the third direction;
a second sidewall formed from a portion of the at least one inner trench sidewall and having a thickness (T) dimension extending along the second direction and a second H dimension extending along the first direction; and
a third sidewall having a third H dimension extending along the first direction and a second L dimension extending along the third direction;
wherein T is less than H;
wherein each of the individual gate structures is physically coupled to the top portion of the first anchor.
16 . The structure of claim 15 further comprising the second trench extending into the substrate in the first direction and the second direction.
17 . The structure of claim 16 further comprising a top portion of the second anchor extending above the major surface of the substrate.
18 . The structure of claim 17 , wherein each of the individual gate structures is physically coupled to the top portion of the second anchor.
19 . The structure of claim 18 , wherein a distance from the first trench to the second trench in the third direction matches a selected length dimension of each of the individual gate structures.
20 . The structure of claim 19 , wherein:
the length dimension extends along the third direction;
each of the individual gate structures further comprises a width dimension extending along the second direction; and
the height dimension is greater than the width dimension.