Methods and systems for filling a gap
Disclosed are methods and systems for filling a gap. An exemplary method comprises providing a substrate to a reaction chamber. The substrate comprises the gap. The method comprises filling the gap with a metal-containing material.
1 . A method of filling a gap, the method comprising
providing a substrate to a reaction chamber, the substrate comprising the gap, the substrate further comprising a proximal surface, the gap comprising a distal end and a sidewall;
executing a plurality of super cycles, a super cycle comprising:
a deposition cycle comprising a precursor pulse and a halogen reactant pulse; and
a step of exposing the substrate to a transformation treatment;
the precursor pulse comprising exposing the substrate to a precursor, the precursor comprising a compound having the general formula ML n , wherein M is a metal, wherein L is an aromatic ligand, and wherein n is an integer from at least 1 to at most 6;
the halogen reactant pulse comprising exposing the substrate to a halogen reactant, the halogen reactant comprising a halogen;
thereby at least partially filling the gap by preferentially forming a metal-containing material on the distal end compared to the proximal surface and the sidewall.
2 . The method according to claim 1 wherein the distal end and the sidewall both comprise a dielectric material.
3 . The method according to claim 1 wherein the distal end and the sidewall both comprise at least one of a metallic material and a semiconducting material.
4 . The method according to claim 1 wherein the aromatic ligand is a substituted or unsubstituted benzene ring.
5 . The method according to claim 4 wherein the ligand is an alkylbenzene.
6 . The method according to claim 1 wherein the metal is molybdenum.
7 . The method according to claim 6 wherein the precursor comprises bis(ethylbenzene)molybdenum.
8 . The method according to claim 1 wherein the halogen reactant comprises an alkyl halide.
9 . The method according to claim 8 wherein the halogen reactant comprises an alkyl iodide.
10 . The method of claim 8 , wherein the halogen reactant has a general formula X a R b C—CX a R′ b , wherein X is a halogen, R and R′ are independently H or an alkyl group, and a and b are independently 1 or 2, so that for each carbon atom a+b=3.
11 . The method according to claim 1 wherein the halogen reactant comprises a bond selected from a X—X bond, a H—X bond, a C—X bond, a P—X bond, a N—X bond, and a S—X bond; wherein X is a halogen.
12 . The method according to claim 1 wherein the deposition cycle further comprises a nitrogen reactant pulse, the nitrogen reactant pulse comprising exposing the substrate to a nitrogen reactant.
13 . The method according to claim 12 wherein the nitrogen reactant comprises NH 3 .
14 . The method according to claim 1 wherein the deposition cycle further comprises an oxygen reactant pulse, the oxygen reactant pulse comprising exposing the substrate to an oxygen reactant.
15 . The method according to claim 1 wherein the deposition cycle further comprises a carbon reactant pulse, the carbon reactant pulse comprising exposing the substrate to a carbon reactant.
16 . An integrated circuit comprising a gap, the gap being filled by means of a method according to claim 1 .
17 . A system comprising:
a reaction chamber;
a metal precursor gas source comprising a metal precursor;
a halogen reactant gas source comprising a halogen reactant; and,
a controller, wherein the controller is configured to control gas flow into the reaction chamber to fill a gap comprised in a substrate by means of a method according to claim 1 .
18 . The method according to claim 1 , wherein the transformation treatment comprises exposing the substrate to a thermal anneal.
19 . The method according to claim 18 wherein the thermal anneal comprises at least one of exposing the substrate to an oxidizing agent, a nitridation agent, a reducing agent, and a noble gas.