Method for depositing silicon-free carbon-containing film as gap-fill layer by pulse plasma-assisted deposition
A Si-free C-containing film having filling capability is deposited by forming a viscous polymer in a gas phase by striking an Ar, He, or N 2 plasma in a chamber filled with a volatile hydrocarbon precursor that can be polymerized within certain parameter ranges which define mainly partial pressure of precursor during a plasma strike, and wafer temperature.
1. A method for filling a patterned recess of a substrate by plasma-assisted deposition of a film having filling capability using a precursor in a reaction space, where a film without filling capability is depositable as a reference film on the substrate using the precursor in the reaction space when the precursor is supplied to the reaction space in a manner providing a first partial pressure of the precursor over the patterned recess of the substrate under first process conditions, said method comprising:
(i) supplying a silicon-free carbon-containing precursor to the reaction space in a manner providing a second partial pressure of the precursor over the patterned recess of the substrate under second process conditions, wherein the second partial pressure is higher than the first partial pressure to the extent of providing filling capability to the film when being deposited under the second process conditions; and
(ii) exposing the patterned recess of the substrate to a plasma under the second process conditions to deposit a silicon-free carbon-containing film having filling capability, wherein during the period of exposing the patterned recess of the substrate to the plasma, a partial pressure of the silicon-free carbon-containing precursor is kept above the first partial pressure, thereby filling the recess in a bottom-up manner,
wherein step (ii) is conducted intermittently in a manner pulsing the plasma, and step (i) is conducted continuously or intermittently without overlapping step (ii) as a step prerequisite for step (ii).
2. The method according to claim 1 , wherein the silicon-free carbon containing precursor is continuously supplied to the reaction space during steps (i) and (ii).
3. The method according to claim 1 , wherein the method comprises an atomic layer deposition recipe.
4. The method according to claim 1 , wherein the silicon-free carbon-containing precursor comprises an unsaturated or cyclic hydrocarbon.
5. The method according to claim 1 , wherein the plasma-assisted deposition is plasma-enhanced CVD deposition.
6. The method according to claim 1 , wherein the plasma-assisted deposition is plasma-enhanced ALD deposition.