MURI Plans

1
MURI Plans

• S. E. Thompson
• March 27, 2005

2
OUTLINE

• SRC and AMD, AMAT, IBM, Intel, TSMC, TI, UMC
  funded device modeling/characterization work
• Plans Single event transient
• Start with SRC strained Si modeling/calibration
• SET on State-of-the-art uniaxial strained Si
  (90-45nm)
• SET on Future strained devices
• Strained Ge transistor
• Strained Si and Ge on (110) wafers

3
Many Ways to Do Strain
Intel 2004 EDL TI 2004 VLSI AMAT 2004 IEDM IBM
2005 VLSI TSMC/Freescalse 2005 Samsung 2005 VLSI
Nitride
a-Si
a-Si
Gate
Gate
Hoyt
Removable film pre-anneal
1-2.5GPa stress film
Even more on high stress layers
Post salicide
4
Strain Being Adopted by All
Source Chipworks 90 nm Intel,IBM,AMD,TI,Fujitsu
5
Why Strain Very Impressive Performance
2004 IEDM Intel
6
Significantly Alters Band Structure/Transport
Biaxial Tension
Uniaxial Longitudinal Compression
Heavy Hole
E
K lt110gt
Uniaxial Longitudinal Tension
Light Hole
Valance Band warping, changes m, m
7
Stress Contours
MPa
Source FLOOPs
8
Device Level Calibration SRC/Intel Funded

• Industrial samples
• 30 nm to 1um Si trasistors from 3 companies
• Unstressed, uniaxial and biaxial stressed wafer
• Bulk and SOI
• Fully depleted SOI /Metal Gate
• High k/metal gate and sub-micron Ge channel
  devices

9
Four-Point Bending Set-Up
Z
Y
X
Bending device
10
Strain Enhanced Mobility Model / Measured
11
6 Band K P Including Confinement
Schrodingers Equation and Poissons Equation
solved self-consistently using the
Finite-Difference Method.
12
Si and Ge Band Structure
13
In and Out-of-Plane Masses (Ge)
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Si and Ge Band Structure on (100) and (110)
Longitudinal compression
Si
Ge
Top Bottom
Top Bottom
(100) (110) hybrid
15
Full Transport Model Calculation of Density of
States
Si is confined in kz direction. 2-dimensional
density of state is given by
And total charge density over all possible bands
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Density of States Mass
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Summary / Next Steps

• First-principles quantum mechanical methods for
  strained Si band structure
• Spatially dependent strain-induced band structure
• Model charge transport and collection due to
  single event in FLOOPS/FLOODS
• Start with existing MURI developed models
• Add strain for Si and Ge transistors