Methods and apparatuses for forming semiconductor devices containing tungsten layers using a tungsten growth suppressant
A method of depositing a metal includes providing a structure a process chamber, and providing a metal fluoride gas and a growth-suppressant gas into the process chamber to deposit the metal over the structure. The metal may comprise a word line or another conductor of a three-dimensional memory device.
1. A method of depositing a metal, comprising:
providing a structure a process chamber; and
providing a metal fluoride gas and two different growth-suppressant gases into the process chamber to deposit the metal over the structure;
wherein:
the metal comprises tungsten;
the metal fluoride gas comprises tungsten hexafluoride;
a first growth-suppressant gas comprises a nitrogen containing gas;
a second growth-suppressant gas comprises gas containing a halogen other than fluorine;
the method comprises an atomic layer deposition process comprising a plurality of unit process cycles, and each unit process cycle comprises a tungsten deposition step, a tungsten hexafluoride purge step, a reducing step and a reducing gas purging step; and
during the tungsten deposition step, initiation of flow the second growth-suppressant gas into the process chamber occurs during a flow of the metal fluoride gas into the process chamber and after the initiation of flow of the metal fluoride gas into the process chamber.
2. A method of depositing a metal, comprising:
providing a structure a process chamber; and
providing a metal fluoride gas and two different growth-suppressant gases into the process chamber to deposit the metal over the structure;
wherein:
the metal comprises tungsten;
the metal fluoride gas comprises tungsten hexafluoride;
a first growth-suppressant gas comprises a nitrogen containing gas;
a second growth-suppressant gas comprises gas containing a halogen other than fluorine;
the method comprises an atomic layer deposition process comprising a plurality of unit process cycles, and each unit process cycle comprises a tungsten deposition step, a tungsten hexafluoride purge step, a reducing step and a reducing gas purging step; and
the growth-suppressant gas is flown into the process chamber occurs during the reducing step.
3. The method of claim 2 , wherein the second growth-suppressant gas is flown into the process chamber occurs between each of the unit process cycles.
4. A method of depositing a metal, comprising:
providing a structure a process chamber; and
providing a metal fluoride gas and two different growth-suppressant gases into the process chamber to deposit the metal over the structure;
wherein:
the metal comprises tungsten;
the metal fluoride gas comprises tungsten hexafluoride;
a first growth-suppressant gas comprises a nitrogen containing gas;
a second growth-suppressant gas comprises gas containing a halogen other than fluorine;
the method comprises an atomic layer deposition process comprising a plurality of unit process cycles, and each unit process cycle comprises a tungsten deposition step, a tungsten hexafluoride purge step, a reducing step and a reducing gas purging step; and
the second growth-suppressant gas is not flown into the process chamber during a first set of the unit process cycles, and the second growth-suppressant gas is flown into the process chamber during a second set of the unit process cycles.