An integrated circuit is formed using an lithographic process including a stage of forming a lithographic layer from a plurality of separately printed pattern layers. Within the integrated circuit there is formed a circuit including at least two devices that are matched devices such that the performance of the circuit is degraded if the match devices deviate from having matched performance characteristics. Dummy contacts 32 (structural features) are provided within the circuit design so as to force allocation of functional contacts (structural features) of the matched devices into the same pattern layer thereby reducing inter-device variation in contact position and/or size.