A method for forming interlevel dielectric layers in multilevel interconnect structures using air as the constituent low-k dielectric material that is compatible with damascene processes without introducing additional process steps. Exemplary tippable shelf assemblies include a support mechanism having a mounting connection coupled with the telecommunication cabinet, and a pivoting tray mechanism having a component connection attached with a telecommunications or electronics component. The first conductive layer pattern may extend along a first direction and the second conductive layer pattern may extend along a second direction. The height of the wedge-shaped light incident part is greater than that of the flat panel. The warp wires are fixed to the holding members such that the first warp wire in each of the pairs has a greater tension applied thereto than the second warp wire in each of the pairs.