Low warpage curing methodology by inducing curvature

Patent metadata

Field	Value
Publication number	US-2023061379-A1
Application number	US-202117410958-A
Country	US
Kind code	A1
Filing date	Aug 24, 2021
Priority date	Aug 24, 2021
Publication date	Mar 2, 2023
Grant date	—

Abstract

Embodiments of methods and apparatus for reducing warpage of a substrate are provided herein. In some embodiments, a method for reducing warpage of a substrate includes: applying an epoxy mold over a plurality of dies on the substrate in a dispenser tool; placing the substrate on a pedestal in a curing chamber, wherein the substrate has an expected post-cure deflection in a first direction; inducing a curvature on the substrate in a direction opposite the first direction; and curing the substrate by heating the substrate in the curing chamber.

First claim

1 . A method for reducing warpage of a substrate, comprising:
applying an epoxy mold over a plurality of dies on the substrate in a dispenser tool; placing the substrate on a pedestal in a curing chamber, wherein the substrate has an expected post-cure deflection in a first direction; inducing a curvature on the substrate in a direction opposite the first direction; and curing the substrate by heating the substrate in the curing chamber.

2 . The method of claim 1 , wherein curing the substrate comprises:
precuring the substrate in a precure chamber by placing the pedestal and the substrate on a heater plate; subsequently moving the pedestal and the substrate to a furnace; and heating the substrate in the furnace.

3 . The method of claim 2 , wherein at least one of:
during curing, the furnace is heated to a temperature of about 165 to about 190 degrees Celsius; or during precuring, the substrate is heated to about 105 to about 125 degrees Celsius.

4 . The method of claim 1 , wherein inducing the curvature on the substrate comprises elevating a central region of the substrate about 1 to about 3 mm with respect to an outer edge of the substrate.

5 . The method of claim 1 , further comprising measuring a temperature of the substrate during curing.

6 . The method of claim 1 , wherein inducing the curvature comprises:
placing the substrate on the pedestal having a central region raised with respect to a peripheral region of the pedestal; and applying a force against the substrate to conform the substrate to the pedestal.

7 . The method of claim 6 , wherein applying the force comprises placing a ring that is weighted on the peripheral region of the substrate to curve the substrate.

8 . The method of claim 1 , wherein the curing chamber is a microwave chamber and curing the substrate comprises:
placing the substrate on the pedestal in the microwave chamber; and directing microwave energy at the substrate to heat the substrate.

9 . The method of claim 8 , wherein the substrate is heated to about 145 to about 165 degrees Celsius in the microwave chamber to cure the substrate.

10 . The method of claim 1 , wherein heating the substrate in the curing chamber is performed for a duration of about 1 to about 2 hours.

11 . A method for reducing warpage of a substrate, comprising:
applying an epoxy mold over a plurality of dies on the substrate in a dispenser tool; placing the substrate on a pedestal in a curing chamber, wherein the substrate has an expected post-cure deflection in a first direction; inducing a curvature on the substrate so that a central region of the substrate is elevated about 1 to about 3 mm with respect to an outer edge of the substrate; and curing the substrate by heating the substrate in the curing chamber.

12 . The method of claim 11 , wherein the curing chamber is a microwave chamber, and the pedestal is made of quartz.

13 . The method of claim 11 , wherein inducing the curvature on the substrate comprises:
at least one of:
placing the substrate on the pedestal that is curved, or
placing a center plate on the pedestal, and placing the substrate on the center plate; and
placing a ring along the outer edge of the substrate to curve the outer edge towards the pedestal.

14 . The method of claim 13 , further comprising placing one or more weights on the ring to provide additional force on the outer edge of the substrate.

15 . A curing chamber for reducing warpage of a substrate with an epoxy layer, comprising:
a chamber body having an interior volume; a pedestal that is transferable and that supports the substrate disposed in the interior volume, wherein the pedestal is configured to induce a curvature on the substrate; a ring disposed along an outer periphery of the substrate and configured to curve an outer edge of the substrate towards the pedestal; and a heat source configured to heat the substrate to a temperature of about 100 to about 200 degrees Celsius.

16 . The curing chamber of claim 15 , further comprising a vacuum source coupled to the pedestal and configured to vacuum chuck the substrate to the pedestal.

17 . The curing chamber of claim 15 , wherein the heat source comprises a microwave source, wherein the pedestal is made of quartz, and wherein the ring is made of quartz.

18 . The curing chamber of claim 17 , further comprising a glass plate disposed between the substrate and the pedestal at a central region of the substrate to elevate the central region with respect to the outer edge of the substrate.

19 . The curing chamber of claim 15 , wherein the curing chamber is a furnace and the heat source is configured to direct hot gas to the interior volume.

20 . The curing chamber of claim 15 , further comprising one or more weights disposed on the ring to provide additional force on the outer edge of the substrate.

Assignees

• Applied Materials Inc

Inventors

• Lim Fang Jie
• Tan Chin Wei
• Su Jun-Liang
• Deng Felix
• Kodumuri Sai Kumar
• Jupudi Ananthkrishna
• Chen Nuno Yen-Chu

Classifications

• H10W90/00

  Package configurations · CPC title

• H10P72/78

  using vacuum or suction, e.g. Bernoulli chucks · CPC title

• H10P72/0436

  mainly by radiation · CPC title

• H10P72/0434

  mainly by convection · CPC title

• H10W72/07337

  using a polymer adhesive, e.g. an adhesive based on silicone or epoxy · CPC title