Package structure including ipd and method of forming the same

An integrated passive device (IPD), comprising:

• a substrate;
• a first connector disposed over a first side of the substrate;
• a through substrate via (TSV) embedded in the substrate and electrically connected to the first connector;
• and
• an RDL structure disposed on a second side of the substrate opposite to the first side and connected to the TSV, wherein the RDL structure comprises:
• a dielectric layer disposed on the second side of the substrate;
• and
• a redistribution layer disposed between the dielectric layer and the substrate and connected to the TSV;
• a guard structure disposed in the dielectric layer and laterally surrounding a connector region;
• a second connector disposed on the redistribution layer and within the connector region;
• wherein the guard structure comprises a trench extending from a top surface of the dielectric layer to a point over the substrate.

A method of forming a package structure, comprising:

• forming an IPD, comprising:
• providing a substrate;
• forming a first connector on a first side of the substrate;
• forming a TSV in the substrate and electrically connected to the first connector;
• forming an RDL structure on a second side of the substrate opposite to the first side and connected to the TSV, wherein forming the RDL structure comprises:
• forming a dielectric layer on the second side of the substrate;
• and
• forming a redistribution layer between the dielectric layer and the substrate and connected to the TSV;
• forming a guard structure in the dielectric layer, wherein the guard structure comprises a trench extending from a top surface of the dielectric layer to a point over the substrate;
• and
• forming a second connector on the redistribution layer within a connector region laterally surrounded by the guard structure;
• electrically bonding the IPD to a package component;
• and
• forming an underfill layer to fill a space between the IPD and the package component.