Kite shaped cavity for embedding material

A semiconductor device comprising:

• a substrate comprising silicon material;
• a gate structure overlaying a first surface region of the substrate, wherein the gate structure comprises a hard mask layer arranged next to a spacer;
• a cavity region positioned within the substrate and adjacent to the first surface region of substrate, the cavity region comprising a tip region and a bottom region, the tip region comprising a first angled sidewall extending directly below a portion of the first surface region, the first angled sidewall being characterized by lattice plane of (1 1 1), the bottom region including a second angled sidewall positioned directly adjacent to a bottom surface of the cavity region, wherein the bottom surface is substantially flat;
• and
• a filling material comprising silicon carbide material positioned at least partially within the cavity region.

A method for fabricating a semiconductor device, the method comprising:

• providing a substrate, the substrate consisting essentially of silicon material;
• defining a first gate region and a second gate region on a surface of the substrate;
• performing ion implantation on the first gate region and the second gate region to form a first doped region and a second doped region;
• forming a first gate structure overlaying the first doped region;
• forming a second gate structure overlaying the second dope region;
• performing a first directional etching process using a first etchant to form a shallow trench characterized by a first height between a cavity region defined between the first gate structure and the second gate structure;
• forming a first offset spacer on a first gate sidewall, the first offset spacer being characterized by a first predefined width, a portion of the first offset spacer being positioned within the shallow trench;
• forming a second offset spacer on a second gate sidewall, the second offset spacer being characterized by a second predefined width, a portion of the second offset spacer being positioned within the shallow trench;
• performing a second directional etching process between the first offset spacer and the second offset spacer into the cavity region;
• removing the first offset spacer and the second offset spacer;
• and
• performing a wet etching process using at least a second etchant for a shaped cavity, the shaped cavity comprising two tip regions interfacing with the substrate and a bottom region, the bottom region being characterized by a second height.