Method and apparatus for using universal cavity wafer in wafer level packaging

Patent metadata

Field	Value
Publication number	US-9847230-B2
Application number	US-201615177723-A
Country	US
Kind code	B2
Filing date	Jun 9, 2016
Priority date	Jun 9, 2015
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

An electronics module assembly is described herein that packages dies using a universal cavity wafer that is independent of electronics module design. In one embodiment, the electronics module assembly can include a cavity wafer having a single frontside cavity that extends over a majority of a frontside surface area of the cavity wafer and a plurality of fillports. The assembly can also include at least one group of dies placed in the frontside cavity and encapsulant that secures the position of the at least one group of dies relative to the cavity wafer. Further, a layer of the encapsulant can cover a backside of the cavity wafer.

First claim

What is claimed is:

1. A method for forming an electronics module assembly, the method comprising:
creating a cavity wafer by etching a wafer to form a single frontside cavity that extends over a majority of a frontside surface area of the cavity wafer and a plurality of fillports;
placing at least one group of dies in the single frontside cavity; and
flowing encapsulant from a backside of the cavity wafer through the fillports and into the single frontside cavity to surround the at least one group of dies.

2. The method of claim 1 , further comprising etching a single backside cavity in the cavity wafer.

3. The method of claim 1 , further comprising
applying heat to the electronics module assembly to cure the encapsulant; and
removing excess encapsulant to the point that the encapsulant fills the backside cavity.

4. The method of claim 1 , further comprising removing a backside of the cavity wafer to expose the fillports.

5. The method of claim 4 , further comprising:
applying heat to the electronics module assembly to cure the encapsulant; and
removing excess encapsulant from the backside of the cavity wafer to form a uniform layer of the encapsulant on the backside of the cavity wafer.

6. The method of claim 5 , wherein a thickness of the layer of encapsulant on the backside of the cavity wafer is determined to reduce bowing from encapsulant in the frontside cavity.

7. The method of claim 5 , further comprising:
removing the layer of encapsulant on the backside of the cavity wafer to reduce bowing from the encapsulant in the frontside cavity.

8. The method of claim 7 , further comprising:
removing a portion of the cavity wafer at the backside with a uniform thickness to further reduce bowing from the encapsulant in the frontside cavity.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Karpman Maurice
• Rickley Michael
• Mueller Andrew
• Mueller Nicole
• Thompson Jeffrey
• Baab Charles

Classifications

• B81B7/0077 Primary

  Other packages not provided for in groups B81B7/0035 - B81B7/0074 · CPC title

• B81C1/00825

  Protect against mechanical threats, e.g. against shocks, or residues (B81C1/00261 take precedence) · CPC title

• B81C2203/0154

  Moulding a cap over the MEMS device · CPC title

• H10W72/9413

  on encapsulations · CPC title

• H10W72/874

  On different surfaces · CPC title