A pressure sensor (10, 49, 140) utilizes the effect of different elastic moduli between layers (20, 21; 36, 38; 53, 54; 123, 124; 146, 147) or sections of different material that are bonded together to form a body (17, 35, 52, 122, 145), so that when the bonded material unit (17, 35, 52, 122, 145) is subjected to a uniform hydrostatic external pressure, the differences in the elastic moduli of each of the materials will cause the materials to deflect in a predictable manner proportional to pressure. The amount of warpage or deflection of the body (17, 35, 52, 122, 145) of material can be measured as a function of pressure. Specifically, two layers of materials (20, 21; 36, 38; 53, 54; 123, 124; 146, 147), such as silicon (20, 38, 54, 123-146) and borosilicate glass (21, 36, 53, 124, 147), which have substantially different elastic moduli can be bonded across an interface surface (40, 55) to form an assembly (17, 35, 52, 122, 145) and when subjected to a substantially uniform pressure on the exterior surfaces the asembly (17, 35, 52, 122, 145) will deflect for indicating applied pressure at relatively high pressure ranges. The bonded material assembly (17, 35, 52, 122, 145) is placed in a fluid to provide a substantially uniform applied hydrostatic pressure on all exposed surfaces of the bonded material assembly (17, 35, 52, 122, 145).