Photonic package and method for forming the same

A method of forming a semiconductor package, comprising:

• forming a micro lens recessed from a top surface of a substrate, wherein a concave area is formed between a surface of the micro lens and the top surface of the substrate;
• depositing a dielectric material that fills the concave area and covers the top surface of the substrate using a spin coating process;
• patterning the dielectric material to leave only a portion of the dielectric material in the concave area using a photolithography process;
• planarizing the dielectric material that has been patterned;
• forming a bonding layer on the planarized dielectric material and over the top surface of the substrate;
• and
• bonding a semiconductor wafer to the substrate via the bonding layer.

A method of forming a semiconductor package, comprising:

• forming a micro lens recessed from a top surface of a substrate, wherein a concave area is formed between a surface of the micro lens and the top surface of the substrate;
• depositing a first gap-fill material that fills a portion of the concave area, wherein the first gap-fill material is deposited by a spin coating process;
• depositing a second gap-fill material that fills a remainder of the concave area and covers the top surface of the substrate, wherein the second gap-fill material is different from the first gap-fill material;
• planarizing the second gap-fill material;
• forming a bonding layer on the planarized second gap-fill material and over the top surface of the substrate;
• and
• bonding a semiconductor wafer to the substrate via the bonding layer.