The NICEWAY EXERCISE

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The NICEWAY EXERCISE

• Dr. Peter Ewen Prof. Rebecca Cheung
• This is taken only by students doing
• MICROELECTRONICS 3

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THE NICEWAY EXERCISE

• PROCESS AND DEVICE SIMULATORS
• IC FABRICATION PROCESSES
• IMPORTANCE OF SIMULATIONS
• THE NICEWAY EXERCISE

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e.g. oxidation time, oxidation temperature, implan
t dose energy
INPUT
PROCESS SIMULATOR
DEVICE STRUCTURE DOPING DENSITIES
ND
gate
field oxide
concentration
OUTPUT
NA
source drain
depth
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device structure, doping densities
INPUT
DEVICE SIMULATOR
ELECTRICAL PROPERTIES
IO

• OUTPUT CHARACTERISTICS
• BREAKDOWN VOLTAGE
• THRESHOLD VOLTAGE
• etc.

OUTPUT
VO
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FABRICATION DETAILS
PROCESS SIMULATOR
device structure doping densities
DEVICE SIMULATOR
ELECTRICAL PROPERTIES
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THE 4 MAIN IC FABRICATION PROCESSES
SiO2
oxidation etching implantation diffusion
silicon
dopant ions
? ? ? ? ? ? ? ? ?
? ?
1000ºC
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SYNOPSIS Inc.
TSUPREM-4 2-D process
simulator MEDICI 2-D
device simulator TAURUS WORKBENCH file handling

environment
Customer list includes Cray Research Xerox
Corp. Motorola Honeywell National
Semiconductor Signetics Texas Instruments RCA Te
ktronix Eaton Corp.
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ADVANTAGES OF COMPUTER SIMULATION IN IC
MANUFACTURE

• LOW COST
• SHORT DEVELOPMENT TIMES
• (FOR DEVELOPING NEW PROCESSES
• OR OPTIMIZING EXISTING ONES)
• 3. YIELDS DETAILED INFORMATION

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Approaching the 2bn factory
Fabrication cost (m)
Source Yoshio Nishi, Vice-president Texas
Instruments
Year
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• Device
• structure
• Structural
• measurements
• Doping
• concentrations
• Concentration
• vs depth 1-D
• profile

Al oxide
poly-Si gate
source drain
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• Electrical properties
• Output
• characteristics
• (IDS vs VDS)
• Gate characteristic
• (ID vs VG - gives VT)
• Breakdown voltage

VT
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Potential contours
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THE NICEWAY EXERCISE

• Three 3-hour lab sessions (starting in week 7)
• location Teaching Lab C (TLC)

• Session 1 Introductory
• exercise
• Session 2 n-channel
• MOS design exercise
• Session 3 p-channel
• CMOS design exercise

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THE NICEWAY EXERCISE

• PREPARATION
• Read sections 1-4 of the manual before first
• session.
• Bring an exercise book to act as a lab-book
  (doesnt have to be anything expensive, but not a
  loose-leaf binder).
• There is a preparation sheet for session 3 that
  must be handed in to EETO see last page of
  handout.