Three-dimensional integrated circuit with top chip including schottky diode body contact
Disclosed structures and methods include a top chip flipped relative to a bottom chip and bonded thereto. On the top chip, dielectric material layers separate a transistor from the bottom chip. The transistor includes source and drain regions, a body region on a channel region between the source and drain regions, and a gate structure adjacent to and between the channel region and the dielectric material layers. An insulator layer is on the transistor opposite the dielectric material layers and includes an opening extending to the body region. Optionally, a semiconductor layer is at the bottom of the opening. A contact extends into the opening to the body region (or to the semiconductor layer thereon, if applicable).
1 . A structure comprising:
a first chip; and
a second chip, wherein the first chip is stacked on the second chip and includes:
first dielectric material layers adjacent to the second chip;
a first insulator layer;
a first transistor including a first active device region stacked vertically between the first dielectric material layers and the first insulator layer,
wherein, within the first active device region, the first transistor includes: a first source region; a first drain region; a first channel region; and a first body region on the first channel region,
wherein the first channel region and the first body region are positioned laterally between the first source region and the first drain region, and
wherein the first transistor further includes a first gate structure within the first dielectric material layers immediately adjacent to a surface of the first active device region at the first channel region; and
a contact to the first body region, wherein the contact is within the first insulator layer and immediately adjacent to another surface of the first active device region opposite the first gate structure.
2 . The structure of claim 1 , wherein the contact is within an opening that extends through the first insulator layer and includes a metallic liner lining the opening and metallic fill material on the metallic liner.
3 . The structure of claim 1 , wherein the contact includes a first portion in an opening that extends through the first insulator layer and a second portion above the first portion and wherein the first chip further includes:
an additional first insulator layer on the first insulator layer and positioned laterally adjacent to the second portion of the contact; and
a source via and a drain via extending through the additional first insulator layer, through the first insulator layer, through first isolation regions, and into the first dielectric material layers to two conductive wires, wherein the two conductive wires are electrically connected to the first source region and the first drain region, respectively.
4 . The structure of claim 1 , wherein the second chip further includes:
a semiconductor substrate;
a second insulator layer on the semiconductor substrate;
a device on the second insulator layer; and
second dielectric material layers on the second insulator layer and extending over the device, wherein a first outermost surface of the first dielectric material layers and a second outermost surface of the second dielectric material layers are bonded.
5 . The structure of claim 4 , wherein the device includes a second transistor having a floating body region.
6 . The structure of claim 4 , wherein the device includes a second transistor having a contacted body region.
7 . The structure of claim 4 , wherein the first dielectric material layers include first conductive wires and vias electrically connected to the first transistor and having at least one first via at the first outermost surface, wherein the second dielectric material layers include second conductive wires and vias electrically connected to the device and having at least one second via at the second outermost surface, and wherein the at least one first via and the at least one second via are bonded and the first transistor and the device are electrically connected.
8 . A structure comprising:
a first chip; and
a second chip, wherein the first chip is stacked on the second chip and includes:
first dielectric material layers adjacent to the second chip;
a first insulator layer; and
a first transistor including a first active device region stacked vertically between the first dielectric material layers and the first insulator layer,
wherein, within the first active device region, the first transistor includes: a first source region; a first drain region; a first channel region; and a first body region on the first channel region,
wherein the first channel region and the first body region are positioned laterally between the first source region and the first drain region,
wherein the first transistor further includes a first gate structure within the first dielectric material layers immediately adjacent to a surface of the first active device region at the first channel region, and
wherein an opening extends through the first insulator layer to the first body region at another surface of the first active device region opposite the first gate structure;
an additional semiconductor layer within the opening immediately adjacent to the first body region; and
a contact within the opening on the additional semiconductor layer.
9 . The structure of claim 8 , wherein the contact includes a metallic liner lining a section of the opening above the additional semiconductor layer and metallic fill material on the metallic liner.
10 . The structure of claim 8 , wherein the contact includes a first portion in a section of the opening above the additional semiconductor layer and a second portion above the first portion and wherein the first chip further includes:
an additional first insulator layer on the first insulator layer and positioned laterally adjacent to the second portion of the contact; and
a source via and a drain via extending through the additional first insulator layer, through the first insulator layer, through first isolation regions, and into the first dielectric material layers to two conductive wires, wherein the two conductive wires are electrically connected to the first source region and the first drain region, respectively.
11 . The structure of claim 8 , wherein the second chip further includes:
a semiconductor substrate;
a second insulator layer on the semiconductor substrate;
a device on the second insulator layer; and
second dielectric material layers on the second insulator layer and extending over the device, wherein a first outermost surface of the first dielectric material layers and a second outermost surface of the second dielectric material layers are bonded.
12 . The structure of claim 11 , wherein the device includes a second transistor having one of a floating body region and a contacted body region.
13 . The structure of claim 8 , wherein the additional semiconductor layer has one of:
a different type conductivity than the first body region; and
a same type conductivity as the first body region at a different conductivity level.
14 . The structure of claim 11 , wherein the first dielectric material layers include first conductive wires and vias electrically connected to the first transistor and having at least one first via at the first outermost surface, wherein the second dielectric material layers include second conductive wires and vias electrically connected to the device and having at least one second via at the second outermost surface, and wherein the at least one first via and the at least one second via are bonded and the first transistor and the device are electrically connected.
15 . A method comprising:
forming a first chip;
forming a second chip;
stacking the first chip on the second chip, wherein the first chip includes:
first dielectric material layers adjacent to the second chip;
a first insulator layer; and
a first transistor between the first dielectric material layers and the first insulator layer, wherein the first transistor includes: a first source region; a first drain region; a first channel region; and a first body region on the first channel region, wherein the first channel region and the first body region are positioned laterally between the first source region and the first drain region; and a first gate structure between the first dielectric material layers and the first channel region;
forming an opening that extends through the first insulator layer to the first body region; and
forming a contact within the opening.
16 . The method of claim 15 , further comprising, before the forming of the contact, forming an additional semiconductor layer in the opening immediately adjacent to the first body region.
17 . The method of claim 15 , wherein the forming of the contact includes:
lining the opening with a metallic liner; and
filling the opening with metallic fill material on the metallic liner.
18 . The method of claim 15 ,
wherein the forming of the first-chip further includes: providing a first semiconductor-on-insulator structure including: a first semiconductor substrate; the first insulator layer on the first semiconductor substrate; and a first semiconductor layer on the first insulator layer, and
wherein the stacking of the first chip on the second chip includes: flipping the first chip relative to the second chip so that the first semiconductor substrate of the first chip.
19 . The method of claim 18 , further comprising, after the stacking and before the forming of the opening, removing the first semiconductor substrate to expose the first insulator layer.
20 . The method of claim 19 , wherein the contact is formed with a first portion in the opening and a second portion above the first portion and wherein the method further comprises:
forming an additional first insulator layer on the first insulator layer positioned laterally adjacent to the second portion of the contact; and
forming a source via and a drain via extending through the additional first insulator layer, through the first insulator layer, through first isolation regions, and into the first dielectric material layers to two conductive wires, wherein the two conductive wires are electrically connected to the first source region and the first drain region, respectively.