Photovoltaic structure and method of fabrication
A photovoltaic device includes one or more features that taken alone or in combination enhance its efficiency. Some embodiments may comprise a tandem solar device in which a top PV cell is fabricated upon a front transparent substrate, that also serves as the top encapsulating substance. The top PV cell including the front encapsulating substance is then bonded (e.g., using adhesive) to a bottom PV cell in order to complete the tandem device. Using the same transparent, insulating element as both front encapsulating substance and a substrate for fabricating the top PV cell, obviates to the need to provide a separate structure (with resulting interfaces) to perform the latter role. For tandem and non-tandem PV devices, a Through-Substrate-Via (TSV) structure may extend through an insulating substrate in order to provide contact with an opposite side (e.g., back electrode). Embodiments may find particular use in fabricating shingled perovskite photovoltaic solar cells.
1. An apparatus comprising a four terminal tandem PV device comprising:
a first thin-film photovoltaic (PV) cell comprising:
a perovskite layer;
a first electrically insulating substrate disposed over a back side of the perovskite layer;
a first through substrate via (TSV) structure extending through the first electrically insulating substrate; and
an electrode extending through the first TSV structure to make electrical contact with the perovskite layer, the electrode covering only a portion of a back side of the first electrically insulating substrate; and
a second thin-film PV cell.
2. An apparatus as in claim 1 wherein the perovskite layer overlaps the second thin-film PV cell.
3. An apparatus as in claim 2 wherein the second thin-film PV cell comprises:
an active layer;
a top electrode layer;
a bottom electrode layer; and
at least one other layer selected from a transport layer, a passivation layer, a back-transfer blocking layer, and an in-situ barrier layer.
4. An apparatus as in claim 1 wherein the first electrically insulating substrate comprises glass.
5. An apparatus as in claim 4 wherein the glass has a thickness of between about 1 μm-3200 μm.
6. An apparatus as in claim 2 wherein the second thin-film PV cell is an Interdigitated Back Contact (IBC) solar cell.
7. An apparatus as in claim 1 wherein the first thin-film PV cell is an Interdigitated Back Contact (IBC) solar cell.
8. An apparatus as in claim 1 wherein the perovskite layer comprises halide perovskite.