Semiconductor device and manufacturing method thereof

A semiconductor device, comprising:

• a semiconductor substrate, and
• a memory tier disposed over the semiconductor substrate, wherein the memory tier comprises:
• paired switch layers and memory layers, wherein, in the pairs, the switch layers and the memory layers are vertically stacked;
• and
• middle electrodes disposed between the memory layers and the switch layers,
• wherein the switch layers comprise a ternary material comprising carbon, germanium, and tellurium, and,
• in the ternary material, a content of carbon is in a range from 10 to 30 atomic percent, a content of germanium is in a range from 10 to 65 atomic percent, and a content of tellurium is in a range from 25 to 80 atomic percent.

A manufacturing method of a semiconductor device, comprising forming a ternary GeCTe material on a substrate,

• wherein forming the ternary GeCTe material comprises:
• applying a first power to a first sputtering target and
• applying a second power to a second sputtering target,
• wherein a material of the first sputtering target is selected from elemental carbon, elemental germanium, elemental tellurium, and a combination thereof,
• a material of the second sputtering target includes a mixture of elements selected from carbon, germanium, and tellurium, and
• in the ternary GeCTe material, a content of carbon is in a range from 15 to 30 atomic percent, a content of germanium is in a range from 10 to 40 atomic percent, and a content of tellurium is in a range from 40 to 70 atomic percent.