The present disclosure describes a method to form a semiconductor device with backside contact structures. The method includes forming a semiconductor device on a first side of a substrate. The semiconductor device includes a source/drain (S/D) region. The method further includes etching a portion of the S/D region on a second side of the substrate to form an opening and forming an epitaxial contact structure on the S/D region in the opening. The second side is opposite to the first side. The epitaxial contact structure includes a first portion in contact with the S/D region in the opening and a second portion on the first portion. A width of the second portion is larger than the first portion.

In some embodiments, the present disclosure relates to an integrated chip that includes a first interconnect dielectric layer arranged over a substrate. An interconnect wire extends through the first interconnect dielectric layer, and a barrier structure is arranged directly over the interconnect wire. The integrated chip further includes an etch stop layer arranged over the barrier structure and surrounds outer sidewalls of the barrier structure. A second interconnect dielectric layer is arranged over the etch stop layer, and an interconnect via extends through the second interconnect dielectric layer, the etch stop layer, and the barrier structure to contact the interconnect wire.

The present disclosure relates to a semiconductor device and a method of fabricating the same, which includes a substrate, a plurality of bit lines, a plurality of first plugs, a first spacer, a second spacer, a plurality of second plugs and a metal silicide layer. The bit lines are disposed on the substrate. The first plugs are disposed on the substrate and separated from the bit lines. The first spacer and the second spacer are disposed between each of the bit lines and the first plugs, and include a first height and a second height respectively. The second plugs are disposed on the first plugs respectively, and the metal silicide layer is disposed between the first plugs and the second plugs, wherein an end surface of the metal silicide layer is clamped between the second spacer and the first spacer.

A semiconductor device with densified dielectric structures and a method of fabricating the same are disclosed. The method includes forming a fin structure, forming an isolation structure adjacent to the fin structure, forming a source/drain (S/D) region on the fin structure, depositing a flowable dielectric layer on the isolation structure, converting the flowable dielectric layer into a non-flowable dielectric layer, performing a densification process on the non-flowable dielectric layer, and repeating the depositing, converting, and performing to form a stack of densified dielectric layers surrounding the S/D region.

A method of processing a substrate that includes: loading the substrate in a processing system, the substrate including a metal having a metal surface and a first dielectric material having a dielectric material surface, the metal surface and the dielectric material surface being at the same level; etching the metal to form a recessed metal surface below the dielectric material surface; selectively forming a self-assembled monolayer (SAM) on the recessed metal surface using a spin-on process; and depositing a dielectric film including a second dielectric material on the dielectric material surface.

Methods and apparatus for processing a substrate are provided herein. For example, a method of processing a substrate comprises a) removing oxide from a metal layer disposed in a dielectric layer on the substrate disposed in a processing chamber, b) selectively depositing a self-assembled monolayer (SAM) on the metal layer using atomic layer deposition, c) depositing a precursor while supplying water to form one of an aluminum oxide (AlO) layer on the dielectric layer or a low-k dielectric layer on the dielectric layer, d) supplying at least one of hydrogen (H.sub.2) or ammonia (NH.sub.3) to remove the self-assembled monolayer (SAM), and e) depositing one of a silicon oxycarbonitride (SiOCN) layer or a silicon nitride (SiN) layer atop the metal layer and the one of the aluminum oxide (AlO) layer on the dielectric layer or the low-k dielectric layer on the dielectric layer.

A semiconductor device includes a lower structure including a substrate, a first interconnection layer extending in a first direction on the lower structure, and including a first metal, a first via contacting a portion of an upper surface of the first interconnection layer and including a second metal, a second via contacting at least a portion of an upper surface of the first via and having a maximum width narrower than a maximum width of the first via, and a second interconnection layer connected to the second via and extending in a second direction. The first interconnection layer has inclined side surfaces in which a width of the first interconnection layer becomes narrower towards an upper region of the first interconnection layer, and the first via has inclined side surfaces in which a width of the first via becomes narrower towards an upper region of the first via.

A semiconductor structure for a DRAM is described having multiple layers of arrays of memory cells. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. The memory cells preferably are thyristors. Methods of fabricating the array are described.

Embodiments of 3D memory devices and methods for forming the same are disclosed. In an example, a 3D memory device includes a substrate, a memory stack including interleaved conductive layers and dielectric layers above the substrate, a structure extending vertically through the memory stack, a first dielectric layer on the memory stack, an etch stop layer on the first dielectric layer, a second dielectric layer on the etch stop layer, a first contact through the etch stop layer and the first dielectric layer and in contact with an upper end of the structure, and a second contact through the second dielectric layer and in contact with at least an upper end of the first contact.

A semiconductor device includes a contact plug forming a signal path electrically connecting a bitline or wordlines and an upper connection pattern to each other, a lower insulating structure includes first and second insulating portions; the contact plug penetrates through the second insulating portion and contacts the upper connection pattern; the first insulating portion includes first and second lower layers, the second lower layer having a thickness smaller than the first lower layer; the second insulating portion includes a first upper layer contacting the second lower layer and covering a portion of an upper surface of the upper connection pattern, and a second upper layer on the first upper layer, the second upper layer having a thickness greater than the first upper layer; and materials of the second lower layer and first upper layer is different from materials of the first lower layer and the second upper layer.