Spacer for trench epitaxial structures
The disclosure relates to a structure and methods of forming spacers for trench epitaxial structures. The method includes: forming a spacer material between source and drain regions of respective first-type gate structures and second-type gate structures; growing source and drain material about the first-type gate structures, confined within an area defined by the spacer material; and growing source and drain material about the second-type gate structures, confined within an area defined by the spacer material.
1. A structure, comprising:
a plurality of first-type gate structures;
a plurality of second-type gate structures;
a first spacer of low-k dielectric material blanket deposited on sidewalls of each of the plurality of first-type gate structures and each of the plurality of second-type gate structures; and
a second spacer of low-k dielectric material formed between the plurality of first-type gate structures and the plurality of second-type gate structures and which defined therebetween are a plurality of trenches for source and drain regions of the plurality of first-type gate structures and the plurality of second-type gate structures, the second spacer of low-k dielectric material located to prevent epitaxial source and drain material from wrapping around the plurality of first-type gate structures and the plurality of second-type gate structures.
2. The structure of claim 1 , wherein the second spacer of low-k dielectric spacer material is a nitride or oxide material.
3. The structure of claim 1 , wherein the first-type gate structures are p-type finFET devices and the second-type gate structures are n-type finFET devices.
4. The structure of claim 1 , further comprising a first capping layer of a first capping material formed on the plurality of first-type gate structures and the plurality of second-type gate structures.
5. The structure of claim 4 , further comprising a second capping layer of a second capping material formed on the first spacer on sidewalls of the first-type gate structures and the second-type gate structures and over the first capping layer.
6. A structure, comprising:
first-type gate structures and second-type gate structures;
a capping layer on the first-type gate structures and the second-type gate structures;
a first spacer material formed on sidewalls of the first-type gate structures and second-type gate structures and over the capping layer;
a second spacer material formed in source and drain regions between the first-type gate structures and the second-type gate structures; and
a source and drain material formed about the first-type gate structures, confined within an area defined by the second spacer material, and the source and drain material formed about the second-type gate structures, confined within an area defined by the second spacer material,
wherein the second spacer material is located to prevent shorting between adjacent ones of the plurality of first-type gate structures and the plurality of second-type gate structures due to a spacing of fins.
7. The structure of claim 6 , wherein the second spacer material is a low-k dielectric material which defines trench structures for the source and drain material of the first-type gate structures and the second-type gate structures.
8. The structure of claim 7 , wherein the second spacer material is nitride or oxide material.
9. The structure of claim 8 , wherein the first-type gate structures are p-type devices and the second-type gate structures are n-type devices.
10. The structure of claim 6 , wherein the first-type gate structures are p-type devices and the second-type gate structures are n-type devices.
11. The structure of claim 6 , wherein the first-type gate structures are p-type finFET devices and the second-type gate structures are n-type finFET devices.
12. A structure, comprising:
a first type of gate structures and a second type of gate structures;
a capping layer on the first type of gate structures and the second type of gate structures;
a spacer on sidewalls on the first type of gate structures and sidewalls on the second type of gate structures and over the capping layer; and
a low-k dielectric spacer material around edges of trenches for source and drain regions of the first type of gate structures and the second type of gate structures which confines epitaxial source and drain material from shorting between the adjacent ones of the first type of gate structures and the second type of gate structures,
wherein the low-k dielectric spacer material is formed in a location such that the low-k dielectric spacer material prevents epitaxial overgrowth from wrapping around the first type of gate structures and the second type of gate structures during growing of the source and drain material about the first type of gate structures and growing of the source and drain material about the second type of gate structures.
13. The structure of claim 12 , wherein the low-k dielectric spacer material is on a single side of two of the first-type gate structures and a single side of two of the second-type gate structures.
14. The structure of claim 12 , wherein the first-type gate structures are p-type devices and the second-type gate structures is n-type devices.
15. The structure of claim 12 , wherein the first-type gate structures are p-type finFET devices and the second-type gate structures are n-type finFET devices.
16. The structure of claim 1 , wherein a gate pitch is less than 80 nm.
17. The structure of claim 16 , wherein the second spacer of low-k dielectric material is SiN, SiBCN, SiOCN, or carbon containing nitride.