Intel Corporation

Intel Ndtm US LLC

Guillaume Bouche

Andy Chih-Hung Wei

Sean T Ma

Changyok Park

Jack T Kavalieros

Anand S Murthy

Charles Henry Wallace

Mauro J Kobrinsky

Mohit K Haran

Shaestagir Chowdhury

Hyuk Ju Ryu

Piyush Mohan Sinha

Yang-Chun Cheng

Mwilwa Tambwe

Andy Wei

Methods for fabricating interconnect arrangements of a metallization layer Mx by using stitching that is enabled by subtractive metallization are disclosed. An example method includes providing a metal layer and a collection layer over the metal layer. The method then includes forming openings for two sets of metal lines by performing a first lithographic process to provide, in the collection layer, first openings for a first set of lines, and then performing a second lithographic process to provide, in the collection layer, second openings for a second set of lines. The method further includes performing a third lithographic process to provide a further opening (a stitch opening) that overlaps with at least one of the first openings of a first track and at least one of the second openings of a second track, and, finally, transferring the pattern of the first, second, and stitch openings to the metal layer.

Stitching to enable dense interconnect arrangements

Embodiments described herein may be related to apparatuses, processes, and techniques related to a transistor structure that includes a buried power rail (BPR) located within the transistor structure at a level below a height of one or more of the fins of the transistor structure. The BPR may be located proximate to a bottom substrate of the transistor structure. In embodiments, the transistor structure includes a protective layer, which can include one or more dielectric layers, above the BPR to protect the BPR during stages of transistor structure manufacture. In embodiments, portions of the protective layer may also be used to constrain epitaxial growth during stages of manufacturing of the transistor structure. Other embodiments may be described and/or claimed.

Power rail between fins of a transistor structure

Gate-all-around integrated circuit structures having germanium-diffused nanowire/nanoribbon channel structures, and methods of fabricating gate-all-around integrated circuit structures having germanium-diffused nanowire/nanoribbon channel structures, are described. For example, an integrated circuit structure includes a vertical arrangement of nanowires above a sub-fin structure, wherein individual ones of the vertical arrangement of nanowires include silicon and germanium, and wherein the sub-fin structure has a relatively higher germanium concentration at a top of the sub-fin structure than at a bottom of the sub-fin structure.

Gate-all-around integrated circuit structures having germanium-diffused nanoribbon channel structures

Disclosed herein are source/drain regions in integrated circuit (IC) structures, as well as related methods and components. For example, in some embodiments, an IC structure may include: an array of channel regions, including a first channel region and an adjacent second channel region; a first source/drain region proximate to the first channel region; a second source/drain region proximate to the second channel region; and an insulating material region at least partially between the first source/drain region and the second source/drain region.

Source/drain regions in integrated circuit structures

Discussed herein is gate spacing in integrated circuit (IC) structures, as well as related methods and components. For example, in some embodiments, an IC structure may include: a first gate metal having a longitudinal axis; a second gate metal, wherein the longitudinal axis of the first gate metal is aligned with a longitudinal axis of the second gate metal; a first dielectric material continuously around the first gate metal; and a second dielectric material continuously around the second gate metal, wherein the first dielectric material and the second dielectric material are present between the first gate metal and the second gate metal.

Gate spacing in integrated circuit structures

Techniques to form self-aligned lateral contacts. In an example, a first trench contact contacts a source or drain region of a transistor. A second trench contact includes non-contiguous first and second portions, each portion having a top surface that is co-planar with a top surface of the first trench contact as well as a top surface of the gate structure. A sidewall of the second trench contact is self-aligned to, and interfaces with, a sidewall of the first trench contact. A via extends from the first portion of the second trench contact to an underlying power rail. In some cases, the second portion of the second trench contact extends over a source or drain region of another transistor, without contacting that source or drain region. The fly-over portion of the second trench contact has a maximum height that is shorter than a maximum height of the first trench contact.

Self-aligned lateral contacts

Disclosed herein are transistor arrangements with trench contacts that have two parts—a first trench contact and a second trench contact—stacked over one another. Such transistor arrangements may be fabricated by forming a first trench contact over a source or drain contact of a transistor, recessing the first trench contact, forming the second trench contact over the first trench contact, and, finally, forming a gate contact that is electrically isolated from, while being self-aligned to, the second trench contact. Such a fabrication process may provide improvements in terms of increased edge placement error margin, cost-efficiency, and device performance, compared to conventional approaches to forming trench and gate contacts. The conductive material of the first trench contact may also be deposited over the gate electrodes of transistors, forming a gate strap, to advantageously reduce gate resistance.

Transistor arrangements with stacked trench contacts and gate straps

Discussed herein is device contact sizing in integrated circuit (IC) structures. In some embodiments, an IC structure may include: a first source/drain (S/D) contact in contact with a first S/D region, and a second S/D contact in contact with a second S/D region, wherein the first S/D region and the second S/D region have a same length, and the first S/D contact and the second S/D contact have different lengths.

Device contact sizing in integrated circuit structures

Disclosed herein are methods for fabricating IC structures that include stacked vias providing electrical connectivity between metal lines of different layers of a metallization stack, as well as resulting IC structures. An example IC structure includes a first and a second metallization layers, including, respectively, a bottom metal line and a top metal line. The IC structure further includes a via that has a bottom via portion and a top via portion, where the top via portion is stacked over the bottom via portion (hence, the via may be referred to as a 'stacked via'). The bottom via portion is coupled and self-aligned to the bottom electrically conductive line, while the top via portion is coupled and self-aligned to the top electrically conductive line. The bottom via portion is formed using selective growth, e.g., assisted by a self-assembled monolayer (SAM) material.

Stacked vias with bottom portions formed using selective growth

Methods for fabricating a transistor arrangement of an IC structure by using a placeholder for backside contact formation, as well as related semiconductor devices, are disclosed. An example method includes forming, in a support structure (e.g., a substrate, a chip, or a wafer), a dielectric placeholder for a backside contact as the first step in the method. A nanosheet superlattice is then grown laterally over the dielectric placeholder, and a stack of nanoribbons is formed based on the superlattice. The nanoribbons are processed to form S/D regions and gate stacks for future transistors. The dielectric placeholder remains in place until the support structure is transferred to a carrier wafer, at which point the dielectric placeholder is replaced with the backside contact. Use of a placeholder for backside contact formation allows alignment of contact from the backside to appropriate device ports of a transistor arrangement.

Use of a placeholder for backside contact formation for transistor arrangements

Transistor arrangements fabricated by forming a metal gate cut as an opening that is non-selective to the gate sidewalls are disclosed. The etch process may be used to provide a power rail if the opening is at least partially filled with an electrically conductive material. Once an electrically conductive material has been deposited within the opening to form a power rail, recessing such a material in portions of the power rail that face gate stacks of various transistors may provide further improvements in terms of reduced parasitic capacitance. A mask for a trench contact to be used to electrically couple the power rail to a S/D region of a transistor may be used as a mask when the electrically conductive material of the power rail is recessed to realize a via that is self-aligned to the trench contact.

Buried power rails with self-aligned vias to trench contacts

Disclosed herein are non-planar transistor (e.g., nanoribbon) arrangements having asymmetric gate enclosures on at least one side. An example transistor arrangement includes a channel material shaped as a nanoribbon, and a gate stack wrapping around at least a portion of a first face of the nanoribbon, a sidewall, and a portion of a second face of the nanoribbon. Portions of the gate stack provided over the first and second faces of the nanoribbon extend in a direction parallel to the longitudinal axis of the nanoribbon for a certain distance that may be referred to as a 'gate length.' A portion of the gate stack wrapping around the sidewall of the nanoribbon does not extend along the entire gate length, but, rather, extends over less than a half of the gate length, e.g., about one third of the gate length, thus making the gate enclosure on that sidewall asymmetric.

Non-planar transistor arrangements with asymmetric gate enclosures

Discussed herein are device contacts in integrated circuit (IC) structures. In some embodiments, an IC structure may include: a first source/drain (S/D) contact; a gate contact, wherein the gate contact is in contact with a gate and with the first S/D contact; and a second S/D contact, wherein a height of the second S/D contact is less than a height of the first S/D contact.

Device contacts in integrated circuit structures

Disclosed herein are methods for manufacturing an integrated circuit (IC) structure, e.g., for manufacturing a metallization stack portion of an IC structure, with one or more self-aligned vias integrated in the back end of line (BEOL), and related semiconductor devices. The methods may employ direct metal etch for scaling the BEOL pitches of the metallization layers. In one aspect, an example method results in fabrication of a via that is self-aligned to both a metal line above it and a metal line below it. Methods described herein may provide improvements in terms of one or more of reducing the misalignment between vias and electrically conductive structures connected thereto, reducing the RC delays, and increasing reliability if the final IC structures.

Growing community of inventors

Portland, OR, United States of America

Guillaume Bouche