Transcript ESD Protection In Microwave Device

ESD Protection In Microwave Device
2003-21649
이민규
Contents
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Introduction
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Material considerations
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Degradation & Failure
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MESFET, MODFET, HEMT, HBT
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Requirements for ESD protection circuits
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ESD protection circuits & devices
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Conclusions
Introduction
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ESD (Electrostatic Discharge)
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순간적으로 많은 전하가 이동하므로 반도체 소자들에게 큰
손상을 유발
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대부분 소자의 제작과정이나 패키징 또는 검사과정에서 발생
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이미 실리콘 반도체에서는 중요한 Reliability aspect
ESD in Microwave Device
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높은 동작 주파수
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화합물 반도체
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ESD 문제에 더욱 민감한 성질을 지님
Material considerations (1)
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Melting point & thermal
conductivity of
compound
semiconductors is lower
than of silicon.
“Heat up faster and melt
earlier”
Their susceptibility to
ESD is higher as
compared to silicon.
Material considerations (2)
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The melt thresholds for
the compound
semiconductor devices
are about a decade
lower than for Si devices.
The burn out of
compound
semiconductors will
occur at lower energies.
(related to the defect
density)
Degradation & Failure (1)
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The lateral material migration across the GaAs
surface -> inter electrode short circuiting bridge
Contact spiking is caused by focused current
flow -> filament penetrates junction (short)
Charge injection and oxide degradation and
breakdown (related to the defect density)
Degradation & Failure (2)
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Filamentation in the semiconductor material -> A
current flow in a localized region creates a melt
filament (leads to increased leakage current by a
resistive path / shorted junction)
Degradation effects related to electromigration in
two or three element compound S.C. -> the
evaluation of the surface condition is even more
complex
MESFET Degradation (1)
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Lateral material
migration
Inter-diffusion
between gold-based
metal and GaAssubstrate (Ohmic
contact)
Contact spiking
Gate blow-off
(Schottky-contact)
MESFET Degradation (2)
Gate blow-off in MESFET
Degradation of ohmic contact
MESFET Degradation (3)
Ref. Ragle Dwayne, Ken Decker, and Matthew Loy, “ESD EFFECTS ON GaAs MESFET
LIFETIME, IEEE/IRPS, 1993.
MESFET Degradation (4)
MODFET Degradation (1)
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The deconfinement
of the 2-DEG
Formation of a
potential barrier
These two effects
will result in
decrease in sourcedrain current.
Ref. W.T. Anderson, A. Christou, F.A. Buot, J. Archer, G. Bechtel, H. Cooke, Y.C. Pao,
M. Simons, and E.W. Chase, “Reliability of discrete MODFETs : Life testing,
Radiation effects, and ESD”, IEEE/IRPS, 1988.
MODFET Degradation (2)
HEMT Degradation
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Inter-diffusion of the
gold-based ohmic
contact metallization
with the epitaxial nGaAs layer affected by
hot electrons.
WSi2-diffusion barrier
and Au top layer ->
degradation only at Au
contacted the GaAs
HBT Degradation (1)
ESD current path in a HBT
HBT degradation
Carbon doped HBT less degradation than Be doped
HBT Degradation (2)
Ref. Tim Henderson, “Effects of Electrostatic Discharge on GaAs-Based HBTs”, IEEE, 1997.
Requirements for ESD protection circuits
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Have to be integratable with the compound S.C.
fabrication process.
Should switch faster than the high frequency
devices to be protected. (about a decade faster)
Have to be low-parasitic and to be able to switch
high signal levels and very high current densities.
ESD protection circuits & devices
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Diodes for ESD Protection
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The ESD protection level reached is about 1000V
Applicable frequency range is limited to about 10-15GHz
Multi-finger HBTs, planar doped barrier diodes
have very high ESD failure thresholds -> consider
as possible ESD protection clamps
ESD protection – Gas Discharge
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Limited in reaction
time being in the range
of 1ns
Based on the physical
process of carrier
multiplication by
ionization of the gas
molecules
Minimum discharge
voltage is about 250V
(related to geometry)
ESD protection – Field emission
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Active electrical device
with a vacuum channel
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parasitic capacitance
scale down ( < 0.1pF )
Switching times much
lower than 1 ps
No power dissipation in
the channel
Field emitter can
handle current
densities up to
108A/cm2
ESD protection – Diode Protection
Ref. F.M. Yamada, A.K. Oki, E.N. Kaneshiro, M.D. Lammert & A.L. Gutierrez-Aitken,
“ESD Sensitivity Study of Various Diode Protection Circuits Implemented
In A Production 1um GaAs HBT Technology”, EIA, 1999.
ESD protection – Using Short-Stub
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Current waveform in
various ESD have
much lower bandwidth
than microwave region
Designed the input
matching circuit of
Ku-band LNA with a
high pass filter, which
consists of a short
stub
Ref. “Ku-Band Low Noise Amplifier with Using Short-Stub ESD Protection”
ESD protection –Cancellation Circuit
Ref. S. Hyvonen, S. Joshi and E. Rosenbaum, “Cancellation technique to provide ESD
protection for multi-GHz RF inputs”, ELECTRONIC LETTERS 6th Feb. 2003. Vol. 39
Conclusions
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ESD Protection for high frequency compound S.C.
based devices and circuits is more critical as
compared to silicon.
The frequency range up to 10 GHz
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Planar doped barrier diodes, multi-finger HBT are
possible ESD protection devices
The frequency range over 10 GHz
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Field emission diode and triode are possible ESD
protection devices.
References (1)
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K. Bock, “ESD issues in compound semiconductor high-frequency devices and
circuits”, Microelectronics Reliability 38, 1998:1781-1793.
K. Bock, “Properties of GaAs Field Emitter Array Structures for ESD-Protection
of MMIC”.
F.M. Yamada, A.K. Oki, E.N. Kaneshiro, M.D. Lammert & A.L. Gutierrez-Aitken,
“ESD Sensitivity Study of Various Diode Protection Circuits Implemented In A
Production 1um GaAs HBT Technology”, EIA, 1999.
Chang-Kun Park, Min-Gun Kim, Chung-Han Kim, and Songcheol Hong, “KuBand Low Noise Amplifier with Using Short-Stub ESD Protection”, IEEE Radio
Frequency Integrated Circuits Symposium, 2003.
Charles Y. Chu, and G.P. Li, “ESD Performance Optimization of Ballast Resistor
On Power AlGaAs/GaAs Heterojunction Bipolar Transistor Technology”,
EOS/ESD Symposium, 1999:235.
S. Hyvonen, S. Joshi and E. Rosenbaum, “Cancellation technique to provide
ESD protection for multi-GHz RF inputs”, Electronics Letters 6th Feb. 2003:
Vol.39 No.3.
References (2)
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Dwayne Ragle, Ken Decker, and Matthew Loy, “ESD Effects on GaAs MESFET
Lifetime”, IEEE/IRPS, 1993.
W.T. Anderson, A. Christou, F.A. Buot, J. Archer, G. Bechtel, H. Cooke, Y.C.
Pao, M. Simons, and E.W. Chase, “Reliability of Discrete MODFETs: Life Testing,
Radiation Effect, And ESD”, IEEE/IRPS, 1988.
Tim Henderson, “Effects of Electrostatic Discharge on GaAs-Based HBTs”, IEEE,
1997.