Patent ID: 8937361
Filing Date: 2015-01-20
Classification: H01L

Abstract:
1. A microelectronic image sensor assembly, comprising: a microelectronic element having a front face, contacts exposed at the front face, a semiconductor region having a first surface adjacent the front face and the semiconductor region having a rear face remote therefrom, and substantially identical first and second light sensing elements arranged on a planar circuitry portion of the semiconductor region to receive light of first and second different wavelengths, respectively, through the rear face, wherein the semiconductor region has a first portion having a first thickness between the first light sensing element and the rear face and a second portion having a second thickness less than the first thickness between the second light sensing element and the rear face, the first and second thicknesses being selected such that the light of the first and second different wavelengths are able to pass through the first and second portions of the semiconductor region, respectively, and reach the first and second light sensing elements with substantially the same intensity, and wherein the planar circuitry portion is disposed between the light sensing elements and the front face and is configured to electrically couple the light sensing elements to the contacts; the microelectronic element further including a dielectric region at least substantially occupying a space within the semiconductor region overlying at least one of the first or second light sensing elements, wherein the microelectronic element has a substantially planar surface overlying the first and second light sensing elements, and a surface of the dielectric region is exposed at the substantially planar surface; and the semiconductor region further including a wall portion disposed between the first and second portions of the semiconductor region, the wall portion having a wall thickness overlying a level of the semiconductor region defined by the first and second light sensing elements, the wall thickness being greater than the first and second thicknesses and extending from the planar circuitry portion of the semiconductor portion to the rear face at the thickest portion of the semiconductor region, and the wall portion being continuous and consisting of a single material of the semiconductor region, separate from the light sensing elements, from a first outermost surface of the wall portion closest to the first portion to a second outermost surface of the wall portion closest to the second portion.