declare @t1 table (idx int, paymentDte datetime);
insert into @t1 values(1,GETDATE())
insert into @t1 values(2,DATEADD(HH,1,GETDATE()))
insert into @t1 values(3,DATEADD(HH,2,GETDATE()))
insert into @t1 values(4,DATEADD(HH,3,GETDATE()))
insert into @t1 values(5,DATEADD(HH,4,GETDATE()))
insert into @t1 values(6,DATEADD(MI,10,GETDATE()))
insert into @t1 values(7,DATEADD(MI,8,GETDATE()))
insert into @t1 values(8,DATEADD(MI,35,GETDATE()))

select * from @t1 where 
--date
CONVERT(VARCHAR(8), paymentDte, 112) > '20120410' and CONVERT(VARCHAR(8), paymentDte, 112) <= '20120419'
and
--hour
DATEPART(HH,paymentDte) >= ? AND DATEPART(hh,paymentDte) <= ?
and
--minute
DATEPART(MI,paymentDte) >= ? AND DATEPART(MI,paymentDte) <= ?