Yes @Ali that's possible. You just have to add these two flags to your kops create cluster command.
--master-count int32 Set the number of masters. Defaults to one master per master-zone
--master-zones strings Zones in which to run masters (must be an odd number)
In your case:
--master-count 9
--master-zones us-east-1d,us-east-1b,us-east-1c