Semiconductor device having a cavity under lens portion
The present invention relates in one aspect to a semiconductor device ( 10 ), comprising a substrate ( 11 ), a photonic semiconductor layer ( 12 ), a first insulator layer ( 13 ) above the photonic semiconductor layer ( 12 ), and a lens layer ( 14 ) on top of the first insulator layer ( 13 ). A method for fabricating the semiconductor device is also disclosed. The method comprises the steps of forming a substrate, forming a photonic semiconductor layer on the substrate, forming a first insulator layer above the photonic semiconductor layer, and forming a lens layer on top of the insulator layer.
1 . A semiconductor device, comprising:
(a) a substrate;
(b) at least one photonic semiconductor layer;
(c) at least one first insulator layer above said photonic semiconductor layer;
(d) at least one lens layer on top of said first insulator layer, characterized in that:
said lens layer is deposited on said first insulator layer and includes at least one lens portion; and
said first insulator layer includes a cavity beneath said lens portion to suspend said lens portion.
2 . The semiconductor device of claim 1 , wherein said photonic semiconductor layer is capable of emitting an electromagnetic radiation.
3 . The semiconductor device of claim 1 , wherein said photonic semiconductor layer is capable of absorbing an electromagnetic radiation.
4 . The semiconductor device of claim 1 , wherein said semiconductor device is at least one of a photodiode, a light emitting diode, a laser diode and a photovoltaic cell.
5 . The semiconductor device of claim 1 , wherein said lens layer has refractive index within a range of 1.46-2.6.
6 . The semiconductor device of claim 1 , wherein a stack of one or more second insulator layers and dielectric layers is formed between said photonic semiconductor layer and said first insulator layer.
7 . The semiconductor device of claim 6 , wherein said second insulator layers and said dielectric layers are alternately arranged upon one another to form said stack.
8 . The semiconductor device of claim 1 , further comprises two or more electrical connectors for electrically connecting said photonic semiconductor layer to at least one external device.
9 . The semiconductor device of claim 1 , wherein said lens layer includes one or more holes around said lens portion.
10 . The semiconductor device of claim 1 , wherein said cavity has a flat bottom surface.
11 . The semiconductor device of claim 1 , wherein at least 80% of a bottom surface area of said lens portion is exposed to said cavity.
12 . The semiconductor device of claim 1 , wherein said cavity is coaxially aligned with said lens portion.
13 . The semiconductor device of claim 1 , wherein a perimeter of said cavity is at least equal to a perimeter of said lens portion.