ibm t.j. watson research center iii-v epitaxy for low ... · epitaxial strategies enabling low...
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IBM T.J. Watson Research Center
Jeehwan KimResearch Group
http://jeehwanlab.mit.edu
III-V epitaxy for low energy optoelectronics
Jeehwan KimMechanical Engineering
Materials Science and EngineeringResearch Laboratory of Electronics
Microsystem Technology Laboratories
Epitaxial strategies enabling low energy optoelectronics
Si photonic waveguide
antenna enhanced LED photodetector
Thrust 1: Optimization of LED stack• Continued efforts in provision of high p-doped InGaAs active region
Thrust 2: III-V hetero-integration on Si• Application of 2D material based layer transfer for exfoliation and hetero-
integration on Si
MIT growth capabilities
Thomas Swan/Aixtron close-coupled showerhead reactor
Hydride precursors for group IV and V
Unique group IV growth capability
1x6” or 6x2” wafer support
MOCVD reactor in substrate engineering lab at MIT
Target
High p-doping is necessary for improved bandwidth modulation
Challenges:• Obtaining C concentration in
target range > 4E19 cm-3
• Ensuring high dopant activation > 2E19 cm-3
• Maintaining In/Ga composition and growth rate
Growth challenges towards 100 GHz III-V antenna-enhanced nanoLED
Growth strategies:
• grow at low growth temperature, V/III ratio• post growth anneal in N2 to activate dopants (removal of H)• use XRD data to feed back into precursor flow rates for next run
Dopant activation with high temp anneal
qx (nm-1)
qz (n
m-1
)
4.815 4.82 4.825 4.83 4.8356.74
6.76
6.78
6.8
6.82
6.84
6.86
6.88
InP substrate
InGaAs
fully strained
XRD compositional analysis to confirm lattice matched InGaAs
Laser power = 500uWWavelength = 1000nm20X objective
without anneal
with anneal 𝜏𝜏 ≈ 140ps
𝜏𝜏 ≈ 700ps
Time-resolved (UC Berkeley)
High C doping with right In/Ga contents
Proposed structures
SI-InP (substrate)
p-InP (250 nm, 1E18 Zn)
p-InGaAs (70nm, 2e19 C)
n-InP (30 nm, 5E18 Si)
n-InGaAs (20nm, 2E18 Si)
InP cladding (100 nm, UID)
InP (20nm, UID)
InP setback (20 nm, UID)
p-InGaAsP contact (150nm, 5e18 Zn)
SI-InP (substrate)
p-InP (250 nm, 1E18 Zn)
p-InGaAs (70 nm, 2E19 C)
n-InP (30 nm, 5E18 Si)
n-InGaAs (20 nm, 2E18 Si)
InP cladding (100 nm, UID)
InP (20 nm, UID)
InP setback (20 nm, UID)
SI-InP (substrate)
InP (100 nm, UID)
p-InGaAs (70 nm, 2E19 C)
InP (30 nm, UID)
InGaAs (20 nm, UID)
InP (20 nm, UID)
Continued optimization of antenna-enhanced LED structure
Strategy to interointegrate nano-LED on Si: Remote epitaxy
Graphene
GaAsSubstrate
Penetrated covalent field
Van der WaalsField >
???
400 nm
400nm
(100) GaAs Wafer
(100) GaAs Film
(100) GaAs Wafer
Polycrystalline
EBSD map HRTEM
AFM
RMS =0.3 nm
Perfect single-crystalline planar films can be grown on 2D materials
Application: 2D material-based layer transfer (2DLT)
Y. Kim et al., and J. Kim., Nature 544, 340 (2017)
Monolayer graphene + Wafer
= Copy Machine (Film producer)
GaAsfilm
GaAsSubstrate
Remote epitaxy works for any compound materials
GaAs (100) InP (100) GaP (100) GaAs (111) GaN (1000)
W. Kong,…and J. Kim*, Nature Materials (2018)
Polarity governs remote atomic interaction through 2D materialsDFT thermodynamic calculation
Kinetic Monte Carlo simulation
Polarity of 3D materials determines field penetration
Polarity of 2D materials determines field screening
W. Kong,…and J. Kim*, Nature Materials (2018)
Remote heteroepitaxy can reduce dislocation density
Fully strained InGaP on GaAs
exx eyy
Relaxed InGaPon graphene
ex
x
ey
y
ConventionalEpitaxy
Remote epitaxyon graphene
1% strained InGaP on GaAs
Spontaneous relaxation occurs on graphenewithout involvement of dislocation!
4% strainedInP on GaAs
Conventional epitaxy Remote epitaxy
Strained Fully relaxed
2DLT for advanced heterointegration
III-V optoelectronics on Si
InGaAs
InP wafer
Remote epitaxy of InGaAsthrough graphene
InP wafer
InGaAsP bottom contactInP bottom contact
InP claddingInGaAs activeInP cladding
InP top contact
InGaAs top contact
Remote epi of InGaAs LED
InP wafer
Peel
Si photonic waveguide
Antenna enhanced LED (TRANSFERRED) photodetector
Collaborators: Eugene FitzegraldMing Wu
Nanoelectronics Group at MIT
9 Ph.D. students Yunjo Kim, Kuan Qiao, Scott Tan, Seungchan Ryu, Chanyeol Choi, Subin Bang, Kuangye Lu, JatinPatil, Skye Ngo
10 Postdocs Shinhyun Choi, Wei Kong, Sanghoon Bae, Hanwool Yeun, Hyun Kum, Peng Lin, Yeongin Kim, Jaewoo Shim, Sungkyu Kim, Lingping Kong
10 Interns J. Fishman, G. Theopan, Y. Lee, D.Lee, B. Lee, L.
Sponsors
Heterointegration Group
Wafer-scale 2D Materials GroupRemote Epitaxy Group
Neuromorphic Computing Group
GaAs (100)InP (100) GaP (100)GaAs (111)GaN (1000)
0 100 200 300 400 500 600 7000
1
2
3
4
5
0 1 2 3 4
10-11
10-8
10-5
Voltage (V)
Cur
rent
(A)
0 1 2 3 4
Voltage (V)
Nature (2017), Nature Materials (2018)
Nature Materials (2018)
Science (2018)