We present a new data structure for the representation of an integrated circuit layout.It is a modified HV/VH tree using arrays as the primary container in bisector lists and leaf nodes.By grouping and sorting objects within these arrays together with a customized binary search algorithm,our new data structure provides excellent performance in both memory usage and region query speed.Experimental results show that in comparison with the original HV/VH tree,which has been regarded as the best layout data structure to date,the new data structure uses much less memory and can become 30％ faster on region query.