Semiconductor constructions which include metal-containing gate portions and semiconductor-containing gate portions
View Patent ↗Some embodiments include a transistor having a first electrically conductive gate portion along a first segment of a channel region and a second electrically conductive gate portion along a second segment of the channel region. The second electrically conductive gate portion is a different composition than the first electrically conductive gate portion. Some embodiments include a method of forming a semiconductor construction. First semiconductor material and metal-containing material are formed over a NAND string. An opening is formed through the metal-containing material and the first semiconductor material, and is lined with gate dielectric. Second semiconductor material is provided within the opening to form a channel region of a transistor. The transistor is a select device electrically coupled to the NAND string.
1. A semiconductor construction, comprising:
a channel region;
gate dielectric directly against the channel region; the gate dielectric comprising one or more oxides;
a semiconductor-containing gate portion along a first segment of the channel region and spaced from said first segment by at least the gate dielectric; the semiconductor-containing gate portion consisting of conductively-doped semiconductor material;
a metal-containing gate portion along a second segment of the channel region and spaced from said second segment by at least the gate dielectric; the second segment being adjacent the first segment; the metal-containing gate portion being directly against the semiconductor-containing gate portion; and
the semiconductor-containing gate portion, metal-containing gate portion, dielectric material and channel region comprising a transistor.
2. The semiconductor construction of claim 1 wherein the metal-containing gate portion and the semiconductor-containing gate portion are both directly against the gate dielectric.
3. The semiconductor construction of claim 2 wherein the metal-containing gate portion is a first metal-containing gate portion, and further comprising a second metal-containing gate portion directly against the gate dielectric and spaced from the first metal-containing gate portion by the semiconductor-containing gate portion.
4. The semiconductor construction of claim 2 wherein the semiconductor-containing gate portion is a first semiconductor-containing gate portion, and further comprising a second semiconductor-containing gate portion directly against the gate dielectric and spaced from the first semiconductor-containing gate portion by the metal-containing gate portion.
5. The semiconductor construction of claim 1 wherein the metal-containing gate portion and the semiconductor-containing gate portion are both directly against an electrically conductive material, which in turn is directly against the gate dielectric.
6. The semiconductor construction of claim 5 wherein the metal-containing gate portion is a first metal-containing gate portion, and further comprising a second metal-containing gate portion directly against the electrically conductive material and spaced from the first metal-containing gate portion by the semiconductor-containing gate portion.
7. The semiconductor construction of claim 5 wherein the semiconductor-containing gate portion is a first semiconductor-containing gate portion, and further comprising a second semiconductor-containing gate portion directly against the electrically conductive material and spaced from the first semiconductor-containing gate portion by the metal-containing gate portion.
8. The semiconductor construction of claim 1 wherein the channel region is over an upper surface of a base and extends substantially vertically relative to such upper surface.
9. A semiconductor construction, comprising:
a channel region over an upper surface of a silicon-containing base and extending substantially vertically relative to such upper surface;
gate dielectric directly against the channel region;
a semiconductor-containing gate portion along a first segment of the channel region and spaced from said first segment by at least the gate dielectric; the semiconductor-containing gate portion consisting of conductively-doped semiconductor material;
a metal-containing gate portion along a second segment of the channel region and spaced from said second segment by at least the gate dielectric; the second segment being adjacent the first segment; the metal-containing gate portion being directly against the semiconductor-containing gate portion;
the semiconductor-containing gate portion, metal-containing gate portion, dielectric material and channel region comprising a transistor; and
a NAND string electrically coupled with the transistor.
10. The semiconductor construction of claim 9 wherein:
the channel region is configured as a pillar laterally surrounded by the gate dielectric; and
the metal-containing gate portion and the semiconductor-containing gate portion entirely laterally surround said pillar; with the metal-containing gate portion being over the semiconductor-containing gate portion.