Structures with through vias passing through a substrate comprising a planar insulating layer between semiconductor

摘要

A through via contains a conductor (244, 262) passing through a substrate (140). The substrate can be SOI or some other substrate containing two semiconductor layers (140.1, 140.2) on opposite sides of an insulating layer (140B). The through via includes two constituent vias (144.1, 144.2) formed from respective different sides of the substrate by processes stopping on the insulating layer (140B). Due to the insulating layer acting as a stop layer, high control over the constituent vias' depths is achieved. Each constituent via is shorter than the through via, so via formation is facilitated. The conductor is formed by separate depositions of conductive material into the constituent vias from each side of the substrate. From each side, the conductor is deposited to a shallower depth than the through-via depth, so the deposition is facilitated. Other embodiments are also provided.

主权项

1. A manufacturing method comprising:
(1) obtaining a structure comprising: a planar insulating layer having a first planar surface and a second planar surface opposite to the first planar surface; a first semiconductor layer having a planar surface contacting the first planar surface of the planar insulating layer; and a second semiconductor layer having a planar surface contacting the second planar surface of the planar insulating layer; (2) forming one or more through vias each of which passes through the first and second semiconductor layers and the planar insulating layer; and (3) forming a conductor in each through via, the conductor providing a conductive path in the through via between the first and second semiconductor layers; wherein each through via comprises: a respective first via portion passing through the first semiconductor layer and formed in operation (2) by removing part of the first semiconductor layer from a side opposite to the second semiconductor layer; and a respective second via portion passing through the second semiconductor layer and formed in operation (2) by removing part of the second semiconductor layer from a side opposite to the first semiconductor layer; wherein in each through via, the conductor comprises a first conductor portion present in the respective first via portion but not in the respective second via portion, and comprises a second conductor portion present in the respective second via portion but not in the respective first via portion; wherein the method further comprises thinning the second semiconductor layer before forming any second via portion but after forming each first via portion and each first conductor portion.