InP-based monolithically integrated pin/HBT photoreceiver arrays with novel on-chip shielding, to reduce electrical and optical crosstalk, have been fabricated and characterised. The photoreceiver array with on-chip plated gold shielding demonstrated an adjacent-channel crosstalk of < -40dB, which represents a 17dB reduction compared to -23dB in an array without such shielding. The arrays demonstrate bandwidths of 5-7GHz.