A memory film and a semiconductor channel can be formed within each memory opening that extends through a stack including an alternating plurality of insulator layers and sacrificial material layers. After formation of backside recesses through removal of the sacrificial material layers selective to the insulator layers, a metallic barrier material portion can be formed in each backside recess. A molybdenum-containing portion can be formed in each backside recess. Each backside recess can be filled with a molybdenum-containing portion alone, or can be filled with a combination of a molybdenum-containing portion and a metallic material portion including a material other than molybdenum.

Disposed are a semiconductor structure, a manufacturing method thereof and a flash memory. The semiconductor structure includes a substrate, first isolation structures, a gate structure and an oxide layer. The first isolation structures define a first active area in a peripheral region of the substrate. The oxide layer is disposed on the substrate in the first active area and covered by the first isolation structures. The oxide layer and the first isolation structures define an opening exposing the substrate. The gate structure is disposed on the substrate in the first active area and includes a gate dielectric layer disposed in the opening and a gate disposed on the gate dielectric layer. The oxide layer is located around the gate dielectric layer. The width of the bottom surface of the gate is less than that of the top surface of the first active area.

A single poly NVM cell includes a first N-type well region and a second N-type well region spaced apart from each other by a P-type semiconductor layer, a first active region and a second active region disposed in the first N-type well region and the second N-type well region, respectively, a P-channel floating gate transistor including a floating gate disposed in the first active region, a P-type drain region disposed in the first active region, and a P-type junction region disposed in the first active region, wherein the floating gate extends to over the second active region, a P-channel read selection transistor including a read selection gate electrode disposed in the first active region, the P-type junction region disposed in the first active region, and a P-type source region disposed in the first active region, and an interconnection line connecting the first N-type well region to the P-type source region of the P-channel read selection transistor.

The flash memory includes a stacked gate disposed on a substrate. The stacked gate includes an erase gate and two floating gates. Each floating gate has an acute angle pointing toward the erase gate. There is a high electric field formed around the acute angle so that the flash memory can perform an erase mode even at a lower operational voltage. Furthermore, the flash memory does not use any control gate to perform a write mode.

A method for forming a semiconductor structure includes forming a gate electrode layer over a semiconductor substrate, forming a first spacer layer to cover a sidewall of the gate electrode layer, recessing the first spacer layer to expose an upper portion of the sidewall of the gate electrode layer, forming a metal material to cover an upper surface and the upper portion of the sidewall of the gate electrode layer; reacting a semiconductor material of the gate electrode layer with the metal material using an anneal process to form a silicide layer, and removing the metal material after the anneal process.

A semiconductor structure including a semiconductor substrate and at least one patterned dielectric layer is provided. The semiconductor substrate includes a semiconductor portion, at least one first device, at least one second device and at least one first dummy ring. The at least one first device is disposed on a first region surrounded by the semiconductor portion. The at least one second device and the at least one first dummy ring are disposed on a second region, and the second region surrounds the first region. The at least one patterned dielectric layer covers the semiconductor substrate.

A method for forming a semiconductor structure includes forming a gate electrode layer over a semiconductor substrate, forming a first spacer layer to cover a sidewall of the gate electrode layer, recessing the first spacer layer to expose an upper portion of the sidewall of the gate electrode layer, forming a metal material to cover an upper surface and the upper portion of the sidewall of the gate electrode layer; reacting a semiconductor material of the gate electrode layer with the metal material using an anneal process to form a silicide layer, and removing the metal material after the anneal process.

A memory device includes a semiconductor substrate with memory cell and logic regions. A floating gate is disposed over the memory cell region and has an upper surface terminating in opposing front and back edges and opposing first and second side edges. An oxide layer has a first portion extending along the logic region and a first thickness, a second portion extending along the memory cell region and has the first thickness, and a third portion extending along the front edge with the first thickness and extending along a tunnel region portion of the first side edge with a second thickness less than the first thickness. A control gate has a first portion disposed on the oxide layer second portion and a second portion vertically over the front edge and the tunnel region portion of the first side edge. A logic gate is disposed on the oxide layer first portion.

A memory device includes a semiconductor substrate with memory cell and logic regions. A floating gate is disposed over the memory cell region and has an upper surface terminating in opposing front and back edges and opposing first and second side edges. An oxide layer has a first portion extending along the logic region and a first thickness, a second portion extending along the memory cell region and has the first thickness, and a third portion extending along the front edge with the first thickness and extending along a tunnel region portion of the first side edge with a second thickness less than the first thickness. A control gate has a first portion disposed on the oxide layer second portion and a second portion vertically over the front edge and the tunnel region portion of the first side edge. A logic gate is disposed on the oxide layer first portion.

In some implementations, one or more semiconductor processing tools may form a first terminal of a semiconductor device by depositing a tunneling oxide layer on a first portion of a body of the semiconductor device, depositing a first volume of polysilicon-based material on the tunneling oxide layer, and depositing a first dielectric layer on an upper surface and a second dielectric layer on a side surface of the first volume of polysilicon-based material. The one or more semiconductor processing tools may form a second terminal of the semiconductor device by depositing a second volume of polysilicon-based material on a second portion of the body of the semiconductor device. A side surface of the second volume of polysilicon-based material is adjacent to the second dielectric layer.