Semiconductor die mount by conformal die coating

• US 9,252,116 B2
• Filed: 04/01/2014
• Issued: 02/02/2016
• Est. Priority Date: 09/10/2007
• Status: Active Grant

• Current Assignee: Invensas Corporation
• Original Assignee: Invensas Corporation
• Inventors: Crane, Scott Jay, McElrea, Simon J. S., McGrath, Scott, Pan, Weiping, Melcher, De Ann Eileen, Robinson, Marc E.
• Primary Examiner(s): SUN, YU-HSI DAVID
• Application Number:
  US14/242,206
• Publication Number:
  US 20140213020A1
• Time in Patent Office: 672 Days
• Field of Search: 257/777, 257/686, 438/109
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/24145 the bodies being stacked
• CPC Class Codes: H01L 2224/24146 the HDI interconnect connecting to the same level of the lower semiconductor or solid-state body at which the upper semiconductor or solid-state body is mounted
• CPC Class Codes: H01L 2224/27452 Chemical vapour deposition [CVD], e.g. laser CVD
• CPC Class Codes: H01L 2224/29005 Structure
• CPC Class Codes: H01L 2224/29006 Layer connector larger than the underlying bonding area
• CPC Class Codes: H01L 2224/32145 the bodies being stacked
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/83191 wherein the layer connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/8385 using a polymer adhesive, e.g. an adhesive based on silicone, epoxy, polyimide, polyester
• CPC Class Codes: H01L 2224/92247 the second connecting process involving a wire connector
• CPC Class Codes: H01L 2225/0651 Wire or wire-like electrical connections from device to substrate
• CPC Class Codes: H01L 2225/06524 Electrical connections formed on device or on substrate, e.g. a deposited or grown layer
• CPC Class Codes: H01L 2225/06551 Conductive connections on the side of the device
• CPC Class Codes: H01L 23/293 Organic, e.g. plastic
• CPC Class Codes: H01L 23/3171 the coating being directly applied to the semiconductor body, e.g. passivation layer H01L23/3178 takes precedence
• CPC Class Codes: H01L 23/3185 : the coating covering also the sidewalls of the semiconductor body
• CPC Class Codes: H01L 24/24 : of an individual high density interconnect connector
• CPC Class Codes: H01L 24/27 : Manufacturing methods
• CPC Class Codes: H01L 24/29 : of an individual layer connector
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/83 : using a layer connector
• CPC Class Codes: H01L 25/0657 : Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01038 : Strontium [Sr]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits

Abstract

A conformal coating on a semiconductor die provides adhesion between the die and a support. No additional adhesive is necessary to affix the die on the support. The conformal coating protects the die during assembly, and serves to electrically insulate the die from electrically conductive parts that the die may contact. The conformal coating may be an organic polymer, such as a parylene, for example. Also, a method for adhering a die onto a support, which may optionally be another die, includes providing a coating of a conformal between the die and the support, and heating the coating between the die and the support. The conformal coating may be provided on a die attach area of a surface of the die, or on a die mount region of a surface of the support, or on both a die attach area of a surface of the die and on a die mount region of a surface of the support; and the conformal coating may be provided following placement of the die on the support.

Claims

1. A method for affixing a die onto a support, comprising providing a first die having a conformal coating on a surface thereof, providing a support having a conformal coating on a surface thereof, contacting a die attach area of the conformal coating on the first die directly with a die mount region of the conformal coating on the support, wherein the conformal coatings on the surfaces of the die and the support are of polyxylylene polymer material, and accomplishing adhesion of the die attach area with the die mount region of the support by heating at least one of the die attach area of the conformal coating on the first die or the die mount region of the conformal coating on the support to a temperature sufficient to affect adhesion.

2. The method of claim 1 wherein the heating procedure follows the contacting procedure.

3. The method of claim 2 wherein the contacting procedure follows the heating procedure.

4. The method of claim 1, wherein the polyxylylene polymer is a parylene selected from the group consisting of a parylene C, a parylene N, a parylene A, and a parylene SR.

5. The method of claim 4, wherein heating the die attach region includes heating the conformal coating to a temperature of about 120 to 230 degrees Celsius.

6. The method of claim 4, wherein heating the die attach region includes heating the conformal coating to a temperature of about 175 to 200 degrees Celsius.

7. The method of claim 4, wherein heating the die attach region includes heating the conformal coating to a temperature of about 125 to 150 degrees Celsius.

8. The method of claim 4, further comprising applying pressure between the first die and support.

9. The method of claim 8, wherein the pressure is about 5N per square cm.

10. The method of claim 1, further comprising providing a second die having a conformal coating on a surface thereof, contacting a die attach area of the conformal coating of the second die with a die mount region of the first die, and heating the die attach area of the conformal coating of the second die.

11. The method of claim 10, further comprising electrically connecting the first and second die to the support via one of an electrically conductive epoxy or electrically conductive ink.

12. The method of claim 1, wherein the support is a second die.

13. The method of claim 12, further comprising contacting a die attach area of the conformal coating of the second die with a die mount region on a non-die support, and heating the die attach area of the conformal coating of the second die.

14. The method of claim 13, further comprising electrically connecting the first and second die to the support via one of an electrically conductive epoxy or electrically conductive ink.

15. The method of claim 1, wherein the heating comprises heating both the die attach area of the conformal coating on the first die and the die mount region of the conformal coating on the support.