A new architecture to fabricate high-rise fully monolithic three-dimensional Integrated-Circuits (3D-ICs) is described. It has the major advantage over all known prior arts in that it substantially reduces RC-delays and fully eliminates or very substantially reduces the large and bulky electrically conductive Through-Silicon-VIAS in a monolithic 3D integration. This enables the 3D-ICs to have faster operational speed with denser device integration.

The circuit includes a first transistor; a second transistor whose first terminal is connected to a gate of the first transistor for setting the potential of the gate of the first transistor to a level at which the first transistor is turned on; a third transistor for setting the potential of a gate of the second transistor to a level at which the second transistor is turned on and bringing the gate of the second transistor into a floating state; and a fourth transistor for setting the potential of the gate of the second transistor to a level at which the second transistor is turned off. With such a configuration, a potential difference between the gate and a source of the second transistor can be kept at a level higher than the threshold voltage of the second transistor, so that operation speed can be improved.

Methods according to the present disclosure include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming an epitaxial layer on at least the first semiconductor region of the substrate, wherein the epitaxial layer includes a first semiconductor base material positioned above the first semiconductor region of the substrate; forming an insulator region on at least the first semiconductor base material, the trench isolation (TI), and the second semiconductor region; forming a first opening in the insulator over the second semiconductor region; and growing a second semiconductor base material in the first opening, wherein a height of the second semiconductor base material above the substrate is greater than a height of the first semiconductor base material above the substrate.

Methods according to the present disclosure include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming an epitaxial layer on at least the first semiconductor region of the substrate, wherein the epitaxial layer includes a first semiconductor base material positioned above the first semiconductor region of the substrate; forming an insulator region on at least the first semiconductor base material, the trench isolation (TI), and the second semiconductor region; forming a first opening in the insulator over the second semiconductor region; and growing a second semiconductor base material in the first opening, wherein a height of the second semiconductor base material above the substrate is greater than a height of the first semiconductor base material above the substrate.

Method to fabricate high-rise three-dimensional Integrated-Circuits (3D-ICs) is described. It has the major advantage over all the other known methods and prior arts to fabricate or manufacture 3D-ICs in that it substantially reduces RC-delays and fully eliminates or very substantially reduces the large and bulky electrically conductive Through-Silicon-VIAs in monolithic 3D integration. This enables the 3D-ICs to have faster operational speed with denser device integration.

The circuit includes a first transistor; a second transistor whose first terminal is connected to a gate of the first transistor for setting the potential of the gate of the first transistor to a level at which the first transistor is turned on; a third transistor for setting the potential of a gate of the second transistor to a level at which the second transistor is turned on and bringing the gate of the second transistor into a floating state; and a fourth transistor for setting the potential of the gate of the second transistor to a level at which the second transistor is turned off. With such a configuration, a potential difference between the gate and a source of the second transistor can be kept at a level higher than the threshold voltage of the second transistor, so that operation speed can be improved.

Methods according to the present disclosure include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming an epitaxial layer on at least the first semiconductor region of the substrate, wherein the epitaxial layer includes a first semiconductor base material positioned above the first semiconductor region of the substrate; forming an insulator region on at least the first semiconductor base material, the trench isolation (TI), and the second semiconductor region; forming a first opening in the insulator over the second semiconductor region; and growing a second semiconductor base material in the first opening, wherein a height of the second semiconductor base material above the substrate is greater than a height of the first semiconductor base material above the substrate.

Methods according to the present disclosure include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming an epitaxial layer on at least the first semiconductor region of the substrate, wherein the epitaxial layer includes a first semiconductor base material positioned above the first semiconductor region of the substrate; forming an insulator region on at least the first semiconductor base material, the trench isolation (TI), and the second semiconductor region; forming a first opening in the insulator over the second semiconductor region; and growing a second semiconductor base material in the first opening, wherein a height of the second semiconductor base material above the substrate is greater than a height of the first semiconductor base material above the substrate.

Methods of according to the present disclosure can include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming a seed layer on the TI and the second semiconductor region of the substrate, leaving the first semiconductor region of the substrate exposed; forming an epitaxial layer on the substrate and the seed layer, wherein the epitaxial layer includes: a first semiconductor base material positioned above the first semiconductor region of the substrate, and an extrinsic base region positioned above the seed layer; forming an opening within the extrinsic base material and the seed layer to expose an upper surface of the second semiconductor region; and forming a second semiconductor base material in the opening.

A semiconductor device, including: a first layer including monocrystalline material and first transistors, the first transistors overlaid by a first isolation layer; a second layer including second transistors and overlaying the first isolation layer, the second transistors including a monocrystalline material; where the second layer includes at least one through layer via to provide connection between at least one of the second transistors and at least one of the first transistors, where the at least one through layer via has a diameter of less than 200 nm; a first set of external connections underlying the first layer to connect the device to external devices; and a second set of external connections overlying the second layer to connect the device to external devices.