Low-k feature formation processes and structures formed thereby
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsWan-Yi KAO, Chung-Chi KO, Li Chun TE, Hsiang-Wei LIN, Te-En CHENG, Wei-Ken LIN, Guan-Yao TU, Shu Ling LIAO
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Abstract
Semiconductor device structures having low-k features and methods of forming low-k features are described herein. Some examples relate to a surface modification layer, which may protect a low-k feature during subsequent processing. Some examples relate to gate spacers that include a low-k feature. Some examples relate to a low-k contact etch stop layer. Example methods are described for forming such features.
Claims20
A method comprising:
- forming a dielectric layer using an Atomic Layer Deposition (ALD) process, the dielectric layer having an increasing concentration gradient of oxygen in a direction from an initially formed portion of the dielectric layer to a subsequently formed portion of the dielectric layer, the dielectric layer having a decreasing concentration gradient of nitrogen in the direction, the ALD process comprising:
- for a cycle:
- flowing an oxygen source precursor at an oxygen flow rate;
- and
- flowing a nitrogen source precursor at a nitrogen flow rate;
- and
- repeating the cycle a number of times, wherein the oxygen flow rate increases during repeating the cycle the number of times, and the nitrogen flow rate decreases during repeating the cycle the number of times.
-20. (canceled)
A method of manufacturing a semiconductor device, the method comprising:
- pulsing for a first time a first oxygen source precursor into a deposition chamber at a first flow rate;
- after the pulsing for the first time the first oxygen source precursor, pulsing for a first time a first nitrogen source precursor into the deposition chamber at a second flow rate;
- after the pulsing for the first time the first nitrogen source precursor, pulsing for a second time the first oxygen source precursor at a third flow rate different from the first flow rate;
- and
- after the pulsing for the second time the first oxygen source precursor, pulsing for a second time the first nitrogen source precursor into the deposition chamber at a fourth flow rate different from the second flow rate, wherein the pulsing the first oxygen source precursor and the pulsing the first oxygen source precursor form a dielectric layer, the dielectric layer having an increasing concentration gradient of oxygen in a first direction and the dielectric layer having a decreasing concentration gradient of nitrogen in the first direction.
A method of manufacturing a semiconductor device, the method comprising:
- initiating an atomic layer deposition process to form a dielectric layer by initiating a first pulse of Si2Cl6 into a deposition chamber;
- purging the deposition chamber;
- initiating a first pulse of C3H6 into the deposition chamber;
- purging the deposition chamber;
- initiating a first pulse of O2 into the deposition chamber at a first oxygen flow rate;
- purging the deposition chamber;
- initiating a first pulse of NH3 into the deposition chamber at a first nitrogen flow rate;
- purging the deposition chamber;
- initiating a second pulse of Si2Cl6 into the deposition chamber;
- purging the deposition chamber;
- initiating a second pulse of C3H6 into the deposition chamber;
- purging the deposition chamber;
- initiating a second pulse of O2 into the deposition chamber at a second oxygen flow rate higher than the first oxygen flow rate;
- purging the deposition chamber;
- and
- initiating a second pulse of NH3 into the deposition chamber at a second nitrogen flow rate less than the first nitrogen flow rate.
The method of claim 28, further comprising:
- forming a low-k spacer layer on the dielectric layer;
- and
- forming a gate spacer comprising anisotropically etching the low-k spacer layer and the dielectric layer. 3o. (New) The method of claim 29, wherein the dielectric layer has an increasing concentration gradient of oxygen.
Dependencies are inferred from the claim text.