Raised source/drain epi with suppressed lateral epi overgrowth

Abstract

A method of forming raised S/D regions by partial EPI growth with a partial EPI liner therebetween and the resulting device are provided. Embodiments include forming groups of fins extending above a STI layer; forming a gate over the groups of fins; forming a gate spacer on each side of the gate; forming a raised S/D region proximate to each spacer on each fin of the groups of fins, each raised S/D region having a top surface, vertical sidewalls, and an undersurface; forming a liner over and between each raised S/D region; removing the liner from the top surface of each raised S/D region and from in between a group of fins; forming an overgrowth region on the top surface of each raised S/D region; forming an ILD over and between the raised S/D regions; and forming a contact through the ILD, down to the raised S/D regions.

What is claimed is: 
     
         1 . A device comprising:
 a plurality of fins formed on a substrate;   a shallow trench isolation layer formed on the substrate between the plurality of fins;   a gate formed over the plurality of fins;   a gate spacer formed adjacent to each side of the gate;   a raised source/drain (S/D) region formed on each of the plurality of fins proximate to each spacer, each raised S/D region having a top surface and vertical sidewalls;   a liner formed on the sidewalls of each raised S/D region;   an overgrowth region formed on the top surface of each raised S/D region;   an interlayer dielectric (ILD) formed over and between the raised S/D regions; and   a contact formed through the ILD down to the raised S/D regions.   
     
     
         2 . The device according to  claim 1 , wherein the raised S/D region is formed by partial epitaxial growth, and wherein the sidewalls have a vertical plane greater than or equal to 5 nanometers (nm) in length. 
     
     
         3 . The device according to  claim 1 , wherein the raised S/D region is formed of silicon germanium (SiGe), Si phosphorous (SiP), silicon carbon phosphorous (SiCP), or silicon carbon boron (SiCB). 
     
     
         4 . The device according to  claim 1 , wherein the liner is formed of silicon nitride (SiN), silicon dioxide (SiO2), aluminum oxide (Al2O3), hafnium oxide (HfO2), silicon oxynitride (SiON), silicon-carbon-boron-nitrogen (SiCBN), silicon-carbon-oxynitride (SiCON), silicon carbon nitride (SiCN), or silicon boron nitride (SiBN). 
     
     
         5 . The device according to  claim 1 , wherein the overgrowth region is formed by epitaxial growth of one or more layers of Si, silicon germanium (SiGe), and/or silicon carbide (SiC). 
     
     
         6 . A device comprising:
 a first group and a second group of fins extending above a shallow trench isolation (STI) layer, the STI layer surrounding at least a portion of the first group and second group of fins;   a gate over the first and second groups of fins;   a gate spacer on each side of the gate;   a raised source/drain (S/D) region proximate to each spacer on each fin of the first and second groups of fins, each raised S/D region having a top surface, vertical sidewalls, and an undersurface;   an overgrowth region on the top surface of each raised S/D region;   an interlayer dielectric (ILD) over and between the raised S/D regions; and   a contact through the ILD, down to the raised S/D regions.   
     
     
         7 . The device according to  claim 6 , wherein the first group of fins comprise a narrow fin pitch relative to the second group of fins. 
     
     
         8 . The device according to  claim 6 , wherein the sidewalls have a vertical plane greater than or equal to 5 nanometers (nm) in length. 
     
     
         9 . The device according to  claim 8 , wherein the raised S/D region comprises silicon germanium (SiGe), silicon phosphorous (SiP), silicon carbon phosphorous (SiCP), or silicon carbon boron (SiCB). 
     
     
         10 . The device according to  claim 6 , wherein the liner has a thickness of 25 angstroms (Å) to 150 Å. 
     
     
         11 . The device according to  claim 10 , wherein the liner comprises silicon nitride (SiN), silicon dioxide (SiO2), aluminum oxide (Al2O3), hafnium oxide (HfO2), silicon oxynitride (SiON), silicon-carbon-boron-nitrogen (SiCBN), silicon-carbon-oxynitride (SiCON), silicon carbon nitride (SiCN), or silicon boron nitride (SiBN). 
     
     
         12 . The device according to  claim 1 , wherein the overgrowth region is formed by epitaxial growth. 
     
     
         13 . The device according to  claim 12 , wherein the overgrowth region has a thickness of 20 Å to 300 Å. 
     
     
         14 . The device according to  claim 6 , wherein the overgrowth region comprises one or more layers of Si, silicon germanium (SiGe), and/or silicon carbide (SiC). 
     
     
         15 . The device according to  claim 6 , further comprising:
 a replacement metal gate (RMG), the RMG located in a trench between gate spacers.   
     
     
         16 . A device comprising:
 a first group and a second group of fins above a shallow trench   isolation (STI) layer, the STI layer surrounding at least a portion of the first group and second group of fins;   a gate over the first and second group of fins;   a gate spacer on each side of the gate;   a raised source/drain (S/D) region proximate to each spacer on each fin of the first and second groups of fins, the S/D region having a top surface, vertical sidewalls, and an undersurface;   a liner atop and between each raised S/D region;   an epitaxial overgrowth region having a thickness of 20 Å to 300 Å on the top surface of each raised S/D region;   an interlayer dielectric (ILD) layer over and between the raised S/D regions; and   a contact between the ILD, down to the raised S/D regions.   
     
     
         17 . The device according to  claim 16 , wherein the sidewalls have a vertical plane greater than or equal to 5 nanometers (nm) in length. 
     
     
         18 . The device according to  claim 16 , wherein the liner has a thickness of 25 angstroms (Å) to 150 Å. 
     
     
         19 . The device according to  claim 16 , wherein the overgrowth region comprises one or more layers of Si, silicon germanium (SiGe), and/or silicon carbide (SiC). 
     
     
         20 . The device according to  claim 16 , wherein the liner comprises silicon nitride (SiN), silicon dioxide (SiO2), aluminum oxide (Al2O3), hafnium oxide (HfO2), silicon oxynitride (SiON), silicon-carbon-boron-nitrogen (SiCBN), silicon-carbon-oxynitride (SiCON), silicon carbon nitride (SiCN), or silicon boron nitride (SiBN).