THIN SEMICONDUCTOR LAMINA ADHERED TO A FLEXIBLE SUBSTRATE
A semiconductor donor body such as a wafer is implanted with ions to form a cleave plane. The donor wafer is affixed to a polyimide receiver element, for example by applying polyimide in liquid form to the donor wafer, then curing, or by affixing the donor wafer to a preformed polyimide sheet. Annealing causes a lamina to cleave from the donor wafer at the cleave plane. The resulting adhered lamina and polyimide body are not adhered to another rigid substrate and can be jointly flexed.
1 . A flexible structure comprising:
a substantially crystalline semiconductor lamina having a thickness less than about 50 microns;
a polyimide substrate affixed to the semiconductor lamina, wherein one or more layers intervene between the semiconductor lamina and the polyimide substrate,
wherein the substantially crystalline semiconductor lamina and the polyimide substrate can be jointly flexed and wherein the polyimide substrate is not affixed to another rigid substrate.
2 . The flexible structure of claim 1 wherein the semiconductor lamina has a thickness between about 1 and about 20 microns.
3 . The flexible structure of claim 1 wherein the semiconductor lamina is monocrystalline, multicrystalline, or polycrystalline silicon.
4 . The flexible structure of claim 1 wherein at least one electronic device comprises at least a portion of the semiconductor lamina.
5 . The flexible structure of claim 4 wherein infrared detection devices are formed in the semiconductor lamina.
6 . The flexible structure of claim 1 wherein a photovoltaic cell comprises the semiconductor lamina.
7 . A flexible photovoltaic structure comprising:
a substantially crystalline semiconductor lamina having a thickness less than about 50 microns;
a polyimide substrate affixed to the semiconductor lamina, wherein one or more layers intervene between the semiconductor lamina and the polyimide substrate; and
a photovoltaic cell, wherein the photovoltaic cell comprises the semiconductor lamina, wherein the polyimide substrate is not affixed to a rigid substrate.
8 . The photovoltaic structure of claim 7 wherein the semiconductor lamina is monocrystalline, multicrystalline, or polycrystalline silicon.
9 . The photovoltaic structure of claim 7 where the semiconductor lamina has a thickness between about 0.5 microns and about 20 microns.
10 . The photovoltaic structure of claim 7 wherein a conductive layer intervenes between the semiconductor lamina and the polyimide substrate.
11 . The photovoltaic structure of claim 10 wherein the conductive layer comprises a metal layer.
12 . The photovoltaic structure of claim 11 wherein the metal layer comprises aluminum.
13 . The photovoltaic structure of claim 11 wherein the metal layer comprises silver.
14 . The photovoltaic structure of claim 10 wherein a dielectric layer intervenes between the semiconductor lamina and the conductive layer.