Microcap wafer-level package with vias

摘要

A microcap wafer-level package Ä10Ü is provided in which a micro device Ä14Ü is connected to bonding pads Ä16, 18Ü on a base wafer Ä12Ü. A peripheral pad Ä20Ü on the base wafer Ä12Ü encompasses the bonding pads Ä16, 18Ü and the micro device Ä14Ü. A cap wafer Ä24Ü is processed to form wells Ä40, 42Ü of a predetermined depth in the cap wafer Ä24Ü. A conductive material Ä27, 29Ü is made integral with the walls Ä46, 47Ü of the wells Ä40, 42Ü in the cap wafer Ä24Ü. The cap wafer Ä24Ü has contacts Ä30,32Ü and a peripheral gasket Ä22Ü formed thereon where the contacts Ä30,32Ü are capable of being aligned with the bonding pads Ä16, 18Ü on the base wafer Ä12Ü, and the gasket Ä22Ü matches the peripheral pad Ä20Ü on the base wafer Ä12Ü. The cap wafer Ä24Ü is then placed over the base wafer Ä12Ü so as to bond the contacts Ä30, 32Ü and gasket Ä22Ü to the pads Ä16, 18, 20Ü and form a hermetically sealed volume Ä25Ü within the peripheral gasket Ä22Ü. The cap wafer Ä24Ü is thinned to form a "microcap" Ä24Ü. The microcap Ä24Ü is thinned below the predetermined depth until the conductive material Ä27, 29Ü is exposed to become conductive vias Ä26, 28Ü through the cap wafer Ä24Ü to outside the hermetically sealed volume Ä25Ü.