Methods of forming imaging pixel microlenses
AssigneeSemiconductor Components Industries, LLC
InventorChristopher PARKS
Life of this patent
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Abstract
A method of forming a microlens may include using two layers of photoresist. The first photoresist layer may be patterned to form a first portion of a pixel microlens. A second photoresist layer may be patterned on top of the first portion of the pixel microlens. The second photoresist may then be melted so that the second photoresist layer has a curved upper surface. The first and second photoresist layers may combine to form the pixel microlens. The indices of refraction of the first and second photoresist layers may the same or different. The melting point of the second photoresist may be lower than the melting point of the first photoresist.
Claims21
A method of forming a microlens, the method comprising:
- patterning a first photoresist to form a first portion of the microlens;
- forming a second photoresist on the first portion of the microlens;
- and
- heating the second photoresist so that the second photoresist melts and forms a second portion of the microlens.
A method comprising:
- forming a first photoresist layer over an image sensor, wherein the image sensor has a plurality of photosensitive areas;
- patterning the first photoresist layer so that there are a plurality of patterned first photoresist portions, wherein each patterned first photoresist portion covers a respective photosensitive area;
- forming a second photoresist layer over the first photoresist layer;
- patterning the second photoresist layer so that there are a plurality of patterned second photoresist portions, wherein each patterned second photoresist portion covers a respective patterned first photoresist portion;
- and
- heating the plurality of patterned second photoresist portions so that the patterned second photoresist portions melt.
A method of forming a microlens over an imaging pixel, the method comprising:
- using photolithography to pattern a first photoresist to form a first portion of the microlens, wherein the first portion of the microlens has an upper surface;
- using photolithography to pattern a second photoresist to form a patterned photoresist portion on the upper surface of the first portion of the microlens, wherein the patterned photoresist portion has a planar upper surface;
- and
- exposing the patterned photoresist portion to heat so that the patterned photoresist portion melts and forms a curved upper surface.
Dependencies are inferred from the claim text.