L'intégration 3D dans les futurs capteurs d'image · STMicroelectronics 3 ~46,000employees...
Transcript of L'intégration 3D dans les futurs capteurs d'image · STMicroelectronics 3 ~46,000employees...
L'intégration 3D dans les
futurs capteurs d'image
Assemblée Générale IRT Nanoelec
D Thomas
05/03/2019
Plan de la présentation
• ST: qui sommes nous?
• Les imageurs chez ST
• L’intégration 3D pour les imageurs: contribution IRT, réalisations
• Les défis à venir
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STMicroelectronics 3
~46,000 employees worldwide
~ 7,400 people working in R&D
11 manufacturing sites
Over 80 sales & marketing offices
Among the world’s largest semiconductor companies
Serving over 100,000 customers across the globe
2018 revenues of $9.66B, with year-on-year growth of 15.8%
Listed: NYSE, Euronext Paris and Borsa Italiana, Milan
Signatory of the United Nations Global Compact (UNGC),
Member of the Responsible Business Alliance (RBA)
As of December 31, 2018
Plan de la présentation
• ST: qui sommes nous?
• Les imageurs chez ST
• L’intégration 3D pour les imageurs: contribution IRT, réalisations
• Les défis à venir
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Imaging Strategy 5
To be the leader in photonic sensors and to become a leader in supplying
specialized image sensor & custom imaging solutionsTime-of-
Flight
Solutions
Specialised
Image
Sensors
Custom
Imaging
Solutions
To provide differentiated Smart Optical Sense & Illumination solutions, thanks to
our advanced pixel & silicon process, optical package & imaging system expertise
Where to find us 6
ImagingSmart Optical Sense & Illumination
Wearable
Appliances
Smart home
Industrial automation
TV/LCD
Medical
Metering
Smartphones
Tablets
Automotive
PC
Robots
ST Pioneer and Leader in Time-of-Flight
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3 Generationsof all-in-one ToF solution deployed since 4 years
>15 OEMsOver 100 phones with ST’s FlightSense™ technology
>30000Evaluation kits deployed
>500 MillionToF units shipped. Mastering end-to-end supply chain
ST is #1 Worldwide Time-of-Flight sensor supplier
VL53L1 3rd generation FlightSense™
• Multi-target detection
• Programmable multi-zone capability
• Cover-glass crosstalk immunity
China
(Shenzhen)
Applications with FlightSense™… making light work
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Camera Assist Ranging & Proximity
Presence, User Detect
Today
Gesture Depth Map & AR/VR
LiDAR
Tomorrow
Plan de la présentation
• ST: qui sommes nous?
• Les imageurs chez ST
• L’intégration 3D pour les imageurs: contribution IRT, réalisations
• Les défis à venir
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3D-Integration: What is the principle?
• From Horizontality to Verticality…
• New system design paradigm: 3D partitioning
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Wire Bonding
BGA
PCB
Interconnect
RDL
Cu/Low-k
Interconnect
Large Foot-print
L2D
2D Chip SetSystem-in-Package
L3D
Die-scale
RDL
Cu/Low-k
Interconnect
TSV
Interconnect
Block-to-Block Length
1 mm ~ 1 cm 10 ~ 100 mm
3D Chip SetSystem-on-chipS
• Key technological benefits
• Significant reduction of interconnects lengths RC delay decrease
• Heterogeneous integration
• Density vs form factor
Single ChipSystem-on-Chip
Additional gain for image sensor11
Back-Side Illuminated
CMOS image sensor2D
Significant reduction of footprint by partitionning circuit reading
below the pixel matrix
Optimized process dedicated to each silicon layer
Area in the logic die available for Added Value
Stacked
CMOS image sensor3D
Density
201620142010
2,5D Imager TSV last (ST)
3D BSI (Sony)
2,5D FPGA (Xilinx) Hybrid Memory Cube
(Micron)
2012
3D CIS GS (Olympus)
Wide I/O Memory/Logic
(Samsung)
3D MEMS (Bosch)
Hig
hLow
Mid
64Gb 3D Dram
(Samsung)
3D BSI HB
(Sony) Interposer for HBM (AMD)
Photonics (ST)Ambiant Light Sensor TSV last (AMS) Year
Many applications: GPU, MEMS, Memories, Photonics and Image Sensors
Jean Michailos & all, invited paper IEDM 2015
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3D Products State of the Art
Image Sensors: strong driver for 3D
technologies 14
System Plus
Different integration schemes have been
developed specifically for CIS market
151st Major BreakthroughTSV enabler of (almost) 3D Wafer Level Camera
Permanent glass carrier
Glue
CMOS image sensor
TSV-last SEM view Back-side SEM view
• Permanent glass carrier bonding
• Via last TSV (CD 70µm, depth 70µm)
• Module form factor as main driver
• Surface gain: 33%
• Thickness gain: 50%
3D Wafer Level Camera
2,5D Wafer Level Camera in mass production in 12’’
3Di for BSI Hybrid Bonding (1)
3Di = an active wafer stacked on second active wafer (W2W) for Imagers
Top : Back-Side illumination image sensor
Bottom : ULSI Cmos image readout and processing
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Face to face interconnections
Double Damascene Copper
stack between top chip last
metal and bottom chip last
metal.
Pitch ≤ 10µm.
Flip
Align
Bond
CMOS
IMG
Back Side
ProcessingThinning, I/O PAD,
Passivation, color, µ-lens…
3Di for BSI Hybrid Bonding (2)
No glue but hybrid molecular bonding
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Top Wafer
Bottom Wafer
Copper bonding
At 3D-via locations
grain growth/migration by anneal
Direct SiO2/SiO2 bonding
Like in non-3D Back-Side Imager (BSI)
silanol SiOH-SiOH then siloxane Si-O-Si after anneal
Top Ox
Bot Ox
Top Cu
Bot Cu
Via HBV
Bot.
Via HBV
top
3D main challenge - Process flow challenges (1)
• Complex process flow mixing different technology.
• Wafer to wafer alignment criticality.
• Bonding interface quality challenge.
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YinYang – 93D Demo
• 93D: stacked approach of Pixel array & ISP
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Computer Vision system:• Face identification
• Gender identification
• Age estimation
• Happiness estimation
• …
Plan de la présentation
• ST: qui sommes nous?
• Les imageurs chez ST
• L’intégration 3D pour les imageurs: contribution IRT, réalisations
• Les défis à venir
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Further step: Three layers stacking21
Sony ISSCC 2017 and TechInsights May 2017
Frame buffer
in a CMOS
image sensor
High speed
pixel read and
slow output
High speed
binning mode
for movie
Oxide-Oxide
DIECT Bonding +
TSV
Oxide- oxide bonding
Oxide- oxide bonding
Further interconnects density increase
Bonding Challenges ? 22
• First generation of 3D image sensor product is based on ~7 µm pitch
• High density hybrid bonding (1 µm ≤ pitch ≤ 2 µm) could reduce footprint
IMEC:
hybrid bonding 1.8 µm WtW
CEA-EVG :
hybrid bonding 1 µm WtW
Jan 2017 Nov 2017
Bonding Tool
capability
• 1µm pitch requires 50nm precision accuracy
Process integration
• Cu microstructure impact on bonding
• Copper dilatation to be checked for small pad size
• Evaluate impact of wafer to wafer misalignment effect on Cu diffusion
FlightSense™ leveraging ST ecosystem 23
Proximity &
Ranging
User detection
Open.Software
• License SW for single-use on specific
target hardware (STM32 Nucleo
Development Board)
• Click through license on website
STM32 Open
Development
Environment
Algorithms
Sensor fusion
Ultra-low power
connectivity