![Page 1: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/1.jpg)
Using Low Cost of Ownership Direct Bonding Technologies For MEMS Applications
Sitaram ArkalgudVP – 3D Applications, Invensas Corporation
![Page 2: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/2.jpg)
Outline
• Background: ZiBond and DBI
• Key MEMS Requirements
• ZiBond and DBI Attributes
• Summary
![Page 3: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/3.jpg)
Background: ZiBond® & DBI®
![Page 4: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/4.jpg)
Corporate Overview
Incorporated: 1990
Headquarters: San Jose, California
Nasdaq listed: TSRAShares Outstanding: ~52 Million
Employees: ~270 (~210 Engineers)
2015 Revenue: $273 Million
2015 Net Income: $117 Million
Mission: Invent, develop, and commercialize electronic interconnect, imaging, and learning technologies to enable efficient, intelligent devices everywhere.
![Page 5: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/5.jpg)
Over 25 Years of Leadership inInnovation & Technology Licensing
Develops novel semiconductor packaging & interconnect solutions for memory, mobile, computing, and smart
object applications.
Develops software and hardware-accelerated computational imaging,
computer vision and biometrics solutions for multiple applications.
Parent Company: Founded in 1990, manages licensing for Tessera’s subsidiaries.
Acquired in August 2015
![Page 6: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/6.jpg)
ZiBond® and DBI® Process : Leverages Existing Infrastructure
CHIPWORKS CONFIDENTIALAll content © 2013, Chipworks Inc. All rights reserved.11
9
Sony IMX135 13-Mpixel CMOS Image Sensor
SEM cross-section of stacked dies
image sensor
image processor
bonding interface
Ⴗ 90-nm back-illuminated sensor bonded face-to-face with 65-nm image processor
Ⴗ “up & over” TSVs filled with Cu & appear to be filled simultaneously
SEM cross-section of TSVs
Cu
Cu
Courtesy Chipworks
ZiBond® DBI®
Courtesy Chipworks
Homogenous BondingDielectric - Dielectric(eg. SiO2-SiO2)
Oxide Si
Si
Hybrid BondingOxide to Oxide with Interconnect (eg. Cu/SiO2 -Cu/SiO2)
InterconnectSi
Si
![Page 7: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/7.jpg)
ZiBond Bond Energy
8
0
1000
2000
3000
4000
5000
0 1 2 3 4
Time (Hours)
Bon
d En
ergy
(mJ/
m^2
)
250C200C150C100C50C21C
Minimum bond energy for post bond
fabrication
Fracture Strength of Silicon
ZiBond® Bond Energy
Low Distortion Dielectric Bonding Very High Bond Energy at Very Low Temperature
![Page 8: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/8.jpg)
DBI® Hybrid Bonding Uniqueness
Cross-Section after Pick/Place (example)
Heating Closes Recess (~ 1 nm / 50ºC) Further Heating Compresses Metal w/out External Pressure
Spontaneous Chemical Reaction with By products Diffusing Away from Bond Interface
Electrical Interconnections at Low Temperature without External Pressure Minimizes Stress and Cost of
Ownership
![Page 9: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/9.jpg)
ZiBond® and DBI® Have Widespread Applicability
Die to Wafer (D2W) Bonding
Die to Die (D2D) Bonding
MEMS(MEMS+Cap Wafer, MEMS+Logic)
DRAM(Multi-Die 3D Stacking)
Image Sensor(Image Sensor + Logic)
RF(RF IC + ASIC)
2.5D Logic + Memory(CPU/GPU + Stacked Memory)
Fingerprint Sensor(Image Sensor + Logic)
Wafer to Wafer (W2W) Bonding
Current ZiBond and/or DBI Licensees*: Sony, Silanna Semiconductor (acq. by Qualcomm), Raytheon, Novati, Fraunhofer, Tezzaron, Sandia and MIT LL
* Licensed to ZiBond and/or DBI
![Page 10: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/10.jpg)
Key MEMS Requirements
![Page 11: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/11.jpg)
Example MEMS Process Flow*
• „Typical“ flow requires two bond steps
• Variety of bond options– Si Fusion– Anodic– Transient Liquid Phase– Eutectic– Metal
thermocompression– Others ...
Handle Wafer with cavity
MEMS Device Wafer
Wafer Bond 1:Handle to
MEMS
MEMS Device Definition CMOS Wafer
Wafer Bond 2:MEMS to
CMOS
Bond pad expose,
Packaging
* Adapted from “Applying the CMOS Test Flow to MEMS Manufacturing” Mike Daneman, InvenSense, Inc. (http://www.meptec.org/Resources/2%20-%20InvenSense.pdf)
![Page 12: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/12.jpg)
Comparing Bond Technologies*Anodic Glass Frit TLP Eutectic Metal
TCBBonding
Temp. (oC)350 - 450 350 - 450 180 - 300 300 - 450 100 - 400
Post Anneal (oC)
NA Same as bonding
Higher than bonding
Same as bonding
NA
Bond Cycle Time (min)
5 – 20 20 – 30 30 – 50 30 – 50 15 - 90
Line Width (µm)
>20 200 – 500 >30 >30 >30
Topography Toler. (µm)
0 1 – 1.5 1 1 0
Leak Rate Low Low Very Low Very low Low
Other High Voltage
Pressure
*Adapted from EVG’s presentation at MEMS Tech XPOT Semicon West 2015
![Page 13: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/13.jpg)
ZiBond and DBI Attributes
![Page 14: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/14.jpg)
Cross-Sectionof
Wafers Bonding
Wafer Alignmentin
Ambientwith
Pick/Place Tool
High Throughput: DBI® Wafer to Wafer Bonding
Wafer to wafer video here
![Page 15: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/15.jpg)
High Throughput: DBI Die to Wafer
Die to Wafer Bonding would be used in MEMS applications where top
and bottom die sizes may not match
Die to wafer video here
![Page 16: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/16.jpg)
Comparing Permeability of Water Vapor in Materials
Ref: D. Stroehle “On the Penetration of Water Vapor into Packages with Cavities and on Maximum Allowable Leak Rates” 15th Annual Proceedings, Reliability Physics Symposium, pp 101-106, 1977.
• Glass seals vary considerably in permeability
– 10 um seal width does not provide adequate sealing
– 100 um may suffice, depending on glass properties
• Metal seals demonstrate orders of magnitude better performance than glass
• Depending on applications, either ZiBond or DBI could be used
100 µm
10 µm
![Page 17: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/17.jpg)
Hermetic Sealing With ZiBond• Die Size: 8x8 mm2• Cavity: 7x7 mm2x 0.1mm• Bond ring: 0.5 mm• MIL STD 883E
Ref: P. Enquist, “Room Temperature Direct Wafer Bonding for Three Dimensional Integrated Sensors”, Sensors and Materials, Vol. 17, No. 6, 2005, p. 307
Helium partial pressure vs post-helium pressure time for ZiBond bonded silicon cavity to silicon wafer
Expect even better hermetic sealing from DBI (comparable to other metal bond technologies)
![Page 18: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/18.jpg)
ZiBond in MEMS
Photograph of a MEMS cavity wafer encapsulated with ZiBond to a glass wafer for a micromirrorapplication. Inset of a singulated die shows the ZiBond surface
![Page 19: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/19.jpg)
Comparing Bond TechnologiesAnodic Glass Frit TLP Eutectic Metal
TCBZiBond DBI
Bonding Temp. (oC)
350 - 450 350 - 450 180 - 300 300 - 450 100 - 400 Room Room
Post Anneal (oC)
NA Same as bonding
Higher than bonding
Same as bonding
NA 75 – 300Post anneal
150 – 300Post anneal
Bond Cycle Time (min)
5 – 20 20 – 30 30 – 50 30 – 50 15 - 90 < 5* < 5*
Line Width (µm)
>20 200 – 500 >30 >30 >30 > 20** > 20**
Topography Toler. (µm)
0 1 – 1.5 1 1 0 0 0
Leak Rate Low Low Very Low Very low Low Low Very Low***
Other High Voltage
Pressure
• Ref: Ziptronix internal data; BEOL development facility (Morrisville, NC)** Preliminary analysis shows equal to/better than Anodic bonding** Ref: Slide 15, equivalent or better than similar metal bonding
![Page 20: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/20.jpg)
Summary
![Page 21: Using Low Cost of Ownership Direct Bonding Technologies For … · 2018. 5. 21. · 21C Minimum bond energy for post bond fabrication Fracture Strength of Silicon ZiBond® Bond Energy](https://reader035.vdocuments.site/reader035/viewer/2022071022/5fd63637a92a464d855bffb2/html5/thumbnails/21.jpg)
Applying ZiBond and DBI to MEMS• Wafer / Die Bonding is a Key Technology Enabler - 2.5D/ 3D IC, Image Sensors, MEMS / Other
Sensors, DRAM, RF …
• ZiBond® and DBI® : Cost effective, low temperature wafer to wafer and die to wafer bonding platforms for wide range of applications
– In high volume production - Multiple generations of leading smartphones and other consumer electronics
– RF: Enables reliable bonding and lowers cost for filters and switches
– Image Sensor: Industry leading backlight illuminated (BSI) image sensor with up to pixel-level interconnect capability
– DRAM: Thinnest and lowest cost 3D DRAM
– 2.5D/3D IC: Eliminates microbumps, underfills and improves performance
• ZiBond® and DBI® for MEMS:
– Alleviates temperature, cycle time, pressure or high voltage concerns with current bonding solutions
– Enables lower cost and reliable MEMS devices