You've got this post marked as solved - perhaps that is why you aren't getting answers.
As far as I know, you use Split to create a one dimensional array of substrings from a string by supplying the string and the character used to separate the substrings. Therefore your commands to dim and populate the array can only populate one row or column and might look like
Code:
Sub aTest()
Dim ar() As String, vm As String
vm = "a,b,c,d,e,f"
ar = Split(vm, ",")
Range(ActiveSheet.Cells(1, 1), ActiveSheet.Cells(1, UBound(ar) + 1)).Value = ar
End Sub