A lateral is gravel packed without a junction in place in a single trip into the wellbore. In particular, arrays and methods are provided for analyzing complex protein mixtures, such as the proteome. The gate dielectric layer is partly removed, thereby a symmetrical opening is formed among the gate conductive layer, the substrate and the gate dielectric layer, and a cavity is formed on end sides of the gate dielectric layer. As a consequence the associations between data items may easily be formed along with associated cluster names formed.