X band, BPF design, PL help!

the filter design will be fabricated in GaAs, with thickness (100—300um). one layer.

specification as bellow:

center frequency: 9.5GHz
1dB BW : 1GHz (9 ~ 10 GHz)
Maximum Insertion losss: -1.5dB
Nominal impedance: 50ohm
Maximum VSWR: 1.5 , typical 1.35
Stopband Attenuation: <-60dB @7590, <-80dB @ 5680

I have try a typical 4 order filter with 2 transmission zero at lower band. the thickness choose 200um. the structure and result as shown.

It still has some distance to the specification.

For the above specification, which filter type and what is the key important for sucess.
Thanks in advance.

It is better to place a notch than going for higher order.

Thanks, so what topology you suggested? or is't possible to insert the notch in the proposed structure?

I will take a time using some open loop structure in this week to try again.

could you give me some more detail guide? thanks again.