Patent ID: 11942504
Assignee: OMNIVISION TECHNOLOGIES, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. An image sensor, comprising:
a logic die, comprising:
a function logic element disposed on a bond side of the logic die; and
a logic oxide array of raised logic oxide features disposed on the bond side of the logic die;
a pixel die stacked on top of the logic die, the pixel die comprising:
a pixel array disposed on a light receiving side of the pixel die; and
a pixel oxide array of raised pixel oxide features disposed on a bond side of the pixel die;
a plurality of outer bonds disposed between an outer region of the logic die and an outer region of the pixel die; and
a plurality of inner bonds formed at an inner region of the image sensor between the pixel oxide array and the logic oxide array, the inner bonds being spaced apart by a plurality of fluidly connected air gaps extending between the logic die and the pixel die,
wherein each fluidly connected air gap has a depth G measured between the logic die and the pixel die of about 1 μm to about 3 μm, each fluidly connected air gap is fluidly connected with at least one air channel located between adjacent outer bonds, the at least one air channel having a width of about 150 μm to about 2000 μm, wherein each raised logic oxide feature and each raised pixel oxide feature has a width W of about 2 μm to about 5 μm, adjacent raised pixel oxide features are spaced apart by a pitch Pp, and adjacent raised logic oxide features are spaced apart by pitch Pl, and
wherein the raised logic oxide features comprise a plurality of logic oxide stripes and the raised pixel oxide features comprise a plurality of pixel oxide stripes, wherein no logic oxide stripe extends in the same direction as any pixel oxide stripe.