425

Filed by: ON Semiconductor Corporation

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12

of the Securities Exchange Act of 1934

Subject Company: AMIS Holdings, Inc.

Commission File No.: 000-50397

This filing contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, statements related to the benefits of the proposed transaction between ON Semiconductor Corporation (“ON”) and AMIS Holdings, Inc. (“AMIS”) and the future financial performance of ON. These forward-looking statements are based on information available to ON and AMIS as of the date of this release and current expectations, forecasts and assumptions and involve a number of risks and uncertainties that could cause actual results to differ materially from those anticipated by these forward-looking statements. Such risks and uncertainties include a variety of factors, some of which are beyond ON’s or AMIS’ control. In particular, such risks and uncertainties include difficulties encountered in integrating merged businesses; the risk that the transaction does not close, including the risk that the requisite stockholder and regulatory approvals may not be obtained; the variable demand and the aggressive pricing environment for semiconductor products; dependence on each company’s ability to successfully manufacture in increasing volumes on a cost-effective basis and with acceptable quality its current products; the adverse impact of competitive product announcements; revenues and operating performance, changes in overall economic conditions, the cyclical nature of the semiconductor industry, changes in demand for our products, changes in inventories at customers and distributors, technological and product development risks, availability of raw materials, competitors’ actions, pricing and gross margin pressures, loss of key customers, order cancellations or reduced bookings, changes in manufacturing yields, control of costs and expenses, significant litigation, risks associated with acquisitions and dispositions, risks associated with leverage and restrictive covenants in debt agreements, risks associated with international operations, the threat or occurrence of international armed conflict and terrorist activities both in the United States and internationally, risks and costs associated with increased and new regulation of corporate governance and disclosure standards (including pursuant to Section 404 of the Sarbanes-Oxley Act of 2002), and risks involving environmental or other governmental regulation. Information concerning additional factors that could cause results to differ materially from those projected in the forward-looking statements is contained in ON’s Annual Report on Form 10-K as filed with the Securities and Exchange Commission (the “SEC”) on February 23, 2007, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other of ON’s SEC filings, and AMIS’ Annual Report on Form 10-K as filed with the SEC on February 28, 2007, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other of AMIS’ SEC filings. These forward-looking statements should not be relied upon as representing ON’s or AMIS’ views as of any subsequent date and neither undertake any obligation to update forward-looking statements to reflect events or circumstances after the date they were made.

This communication is being made in respect of the proposed transaction involving ON and AMIS. In connection with the proposed transaction, ON plans to file with the SEC a Registration Statement on Form S-4 containing a Joint Proxy Statement/Prospectus and each of ON and AMIS plan to file with the SEC other documents regarding the proposed transaction. The definitive Joint Proxy Statement/Prospectus will be mailed to stockholders of ON and AMIS. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE JOINT PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS FILED WITH THE SEC CAREFULLY IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION.


Investors and security holders will be able to obtain free copies of the Registration Statement and the Joint Proxy Statement/Prospectus (when available) and other documents filed with the SEC by ON and AMIS through the web site maintained by the SEC at www.sec.gov. In addition, investors and security holders will be able to obtain free copies of the Registration Statement and the Joint Proxy Statement/Prospectus (when available) and other documents filed with the SEC from ON by directing a request to ON Semiconductor Corporation, 5005 East McDowell Road, Phoenix, AZ, 85008, Attention: Investor Relations (telephone: (602) 244-3437) or going to ON’s corporate website at www.onsemi.com, or from AMIS by directing a request to AMIS Holdings, Inc., 2300 Buckskin Road Pocatello, ID, 83201, Attention: Investor Relations (telephone: (208) 233-4690) or going to AMIS’ corporate website at www.amis.com.

ON and AMIS, and their respective directors and executive officers, may be deemed to be participants in the solicitation of proxies in respect of the proposed transaction. Information regarding ON’s directors and executive officers is contained in its annual proxy statement filed with the SEC on April 11, 2007. Information regarding AMIS’ directors and executive officers is contained in AMIS’ annual proxy statement filed with the SEC on May 24, 2007. Additional information regarding the interests of such potential participants will be included in the Joint Proxy Statement/Prospectus and the other relevant documents filed with the SEC (when available).

Filed below is a presentation to ON investors on December 13, 2007 regarding ON’s proposed acquisition of AMIS.


The Power of
ON Semiconductor
Investor Presentation
December 2007


2
Safe Harbor Statement & Non-GAAP Financial
Measure Information
During the course of this presentation, ON Semiconductor may make projections or
other forward-looking statements regarding future events or its future financial
performance.  The words “estimate,”
“intend,”
“expect,”
“plan,”
or similar expressions are
intended to identify forward-looking statements.  ON Semiconductor wishes to caution
that
such
statements
are
subject
to
risks
and
uncertainties
that
could
cause
actual
events
or results to differ materially.  Important factors relating to our business, including factors
that could cause actual results to differ from our forward-looking statements, are
described in our Form 10-K and other filings with the SEC.  ON Semiconductor assumes
no obligation to update forward-looking statements to reflect actual results or changed
assumptions or other factors.
Some data in this presentation may include non-GAAP financial measures.  You can
find reconciliations of certain of these non-GAAP financial measures to the most directly
comparable measures under generally accepted accounting principles within the
following
presentation
at
our
website
(http://www.onsemi.com)
at
the
“Investors”
section
under the category “Annual Reports/Financial Releases.”


3
This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform
Act of 1995. These forward-looking statements include, but are not limited to, statements related to the benefits of the
proposed transaction between ON Semiconductor Corporation (“ON”) and AMIS Holdings, Inc. (“AMIS”) and the future
financial performance of ON. These forward-looking statements are based on information available to ON and AMIS as
of the date of this release and current expectations, forecasts and assumptions and involve a number of risks and
uncertainties that could cause actual results to differ materially from those anticipated by these forward-looking
statements.
Such
risks
and
uncertainties
include
a
variety
of
factors,
some
of
which
are
beyond
ON’s
or
AMIS’
control.
In
particular,
such
risks
and
uncertainties
include
difficulties
encountered
in
integrating
merged
businesses;
the
risk
that
the transaction does not close, including the risk that the requisite stockholder and regulatory approvals may not be
obtained; the variable demand and the aggressive pricing environment for semiconductor products; dependence on
each
company’s
ability
to
successfully
manufacture
in
increasing
volumes
on
a
cost-effective
basis
and
with
acceptable
quality its current products; the adverse impact of competitive product announcements; revenues and operating
performance, changes in overall economic conditions, the cyclical nature of the semiconductor industry, changes in
demand
for
our
products,
changes
in
inventories
at
customers
and
distributors,
technological
and
product
development
risks, availability of raw materials, competitors' actions, pricing and gross margin pressures, loss of key customers,
order cancellations or reduced bookings, changes in manufacturing yields, control of costs and expenses, significant
litigation, risks associated with acquisitions and dispositions,
risks associated with leverage and restrictive covenants in
debt agreements, risks associated with international operations,
the threat or occurrence of international armed conflict
and terrorist activities both in the United States and internationally, risks and costs associated with increased and new
regulation of corporate governance and disclosure standards (including pursuant to Section 404 of the Sarbanes-Oxley
Act of 2002), and risks involving environmental or other governmental regulation.  Information concerning additional
factors
that
could
cause
results
to
differ
materially
from
those
projected
in
the
forward-looking
statements
is
contained
in ON’s Annual Report on Form 10-K as filed with the Securities and Exchange Commission (the “SEC”) on February
23, 2007, Quarterly Reports on Form 10-Q Current Reports on Form 8-K and other of ON’s SEC filings, and AMIS’
Annual Report on Form 10-K as filed with the SEC on February 28, 2007, Quarterly Reports on Form 10-Q, Current
Reports
on
Form
8-K
and
other
of
AMIS’
SEC
filings.
These
forward-looking
statements
should
not
be
relied
upon
as
representing ON’s or AMIS’
views as of any subsequent date and neither undertake any obligation to update forward-
looking statements to reflect events or circumstances after the date they were made.


4
This communication is being made in respect of the proposed transaction involving ON and AMIS. In
connection with the proposed transaction, ON plans to file with the SEC a Registration Statement on Form S-4
containing
a
Joint
Proxy
Statement/Prospectus
and
each
of
ON
and
AMIS
plan
to
file
with
the
SEC
other
documents
regarding the proposed transaction. The definitive Joint Proxy Statement/ Prospectus will be mailed to stockholders of
ON and AMIS. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE JOINT PROXY
STATEMENT/PROSPECTUS AND OTHER DOCUMENTS FILED WITH THE SEC CAREFULLY IN THEIR ENTIRETY
WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE
PROPOSED TRANSACTION.
Investors and security holders will be able to obtain free copies of the Registration Statement and the Joint
Proxy Statement/Prospectus (when available) and other documents filed with the SEC by ON and AMIS through the
web site maintained by the SEC at www.sec.gov. In addition, investors and security holders will be able to obtain free
copies of the Registration Statement and the Joint Proxy Statement/Prospectus (when available) and other documents
filed with the SEC from ON by directing a request to ON Semiconductor Corporation, 5005 East McDowell Road,
Phoenix,
AZ,
85008,
Attention:
Investor
Relations
(telephone:
(602)
244-3437)
or
going
to
ON’s
corporate
website
at
www.onsemi.com, or from AMIS by directing a request to AMIS Holdings, Inc., 2300 Buckskin Road Pocatello, ID,
83201,
Attention:
Investor
Relations
(telephone:
208-233-4690)
or
going
to
AMIS’
corporate
website
at
www.amis.com.
ON and AMIS, and their respective directors and executive officers, may be deemed to be participants in the
solicitation of proxies in respect of the proposed transaction. Information regarding ON’s directors and executive officers
is
contained
in
its
annual
proxy
statement
filed
with
the
SEC
on
April
11,
2007.
Information
regarding
AMIS’
directors
and
executive
officers
is
contained
in
AMIS’
annual
proxy
statement
filed
with
the
SEC
on
May
24,
2007.
Additional
information regarding the interests of such potential participants will be included in the Joint Proxy
Statement/Prospectus
and
the
other
relevant
documents
filed
with
the
SEC
(when available).


5
A Winning Combination
Over 90 Years of Semiconductor Expertise
World class, high
volume, cost
effective products
Leading standard
products in
Automotive,
Computing,
Consumer and
Communications
end markets
Industry leader in
power management
LTM Revenue:
$1,560MM
LTM EBITDA:
$388MM
LTM Free Cash Flow
(1)
:       $223MM
Leader in analog
and mixed signal
technology and
design
Automotive products
leader
Leading custom
products in Medical,
Mil/Aero and
Industrial end
markets
8-10 years average
product lifespan
LTM Revenue:
$619MM
LTM EBITDA:
$134MM
LTM Free Cash Flow
(1)
:
$25MM
(1)     Free cash flow defined as operating cash flow less capital expenditures.
Manufacturing
synergies
Operating expense
savings
Tax savings
Capital expenditure
reductions
Synergies


6
Transaction Overview
Terms
Each share of AMIS will be exchanged for 1.150 ON shares
Consideration
Stock-for-stock transaction valued at approximately $915 million
Pro Forma
Ownership
74% ON shareholders, 26% AMI shareholders
Board of Directors
Expanded to 8 Members with the addition of Christine King, AMIS CEO
Share Repurchase
Board authorized an additional 20MM share increase to ON’s existing
stock repurchase program.  Total of 50MM shares available, approximately
50% of the shares to be issued in this transaction
Anticipated Close
First half of 2008
Conditions
Approval by ON and AMIS shareholders, customary closing conditions
and regulatory approvals. 
Voting Agreements
Stockholders holding approximately 24% of the voting stock of AMIS and
the executive officers of both companies have entered into voting
agreements in support of the transaction


7
Transaction Rationale
Accelerates ON’s
Analog
Transformation
Expands mixed signal design and product capability
Over
88%
of
AMI’s
custom
products
/
design
wins
are
sole
sourced
Higher margin product portfolio with products that have long product
cycles
Pro Forma LTM gross margins of 40%
Strengthen End
Market Presence and
Gain Entry into
New Markets
Expands presence in automotive, consumer, communications and
industrial end markets
Gain entry into high growth, higher margin medical market and high-
margin Mil/Aero market
Increase value proposition to end customers with both leading standard
and custom products
Leverage ON’s
Operational
Excellence to Drive
Cost Savings
Successful
track
record
of
cost
reduction
and
rationalization
to
improve
profitability of combined business
Utilize advanced sub-micron Gresham fabrication facility to drive cost
savings and extend product roadmap
Consolidate combined company’s manufacturing network
Significant Scale
and Cash Flow
Generation
Pro Forma LTM revenues of $2.2 billion*
Pro Forma LTM EBITDA of $522 million* (with zero synergies)
Pro Forma LTM free cash flow of $248 million*
Potential to accelerate revenue growth of combined companies
Accretive to earnings per share exiting 2008*
•Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor.
Free
cash
flow
defined
as operating cash flow less capital expenditures. Earnings per share excludes amortization of  intangibles


8
Standard
12%
Custom
88%
Standard /
Discrete
49%
Custom /
Integrated
Circuits
51%
LTM Revenue
$1,560MM
/
LTM Revenue
$619MM
LTM Revenue*
$2,179MM
Note:  Charts do not include revenue from manufacturing services.
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor.
Diversified Product Platform
Discrete
65%
Integrated
Circuits
35%
A Leader in Mixed Signal & Analog Technologies


9
Automotive
27%
Mil. / Aero
8%
Medical
17%
Communications
8%
Industrial
25%
Computing
9%
Consumer
6%
Computing
23%
Industrial
13%
Wireless
19%
Networking
7%
Automotive
17%
Consumer
21%
/
Note: Not all segments included.
Charts do not include revenue from manufacturing services.
Balanced End Market Presence
Computing
19%
Industrial
17%
Communications
20%
Mil. / Aero
2%
Consumer
17%
Automotive
20%
Medical
5%
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
On
Semiconductor
and
AMI
Semiconductor.
LTM Revenue
$1,560MM
LTM Revenue
$619MM
LTM Revenue*
$2,179MM


10
ON Market Segments
Automotive and
Power Regulation
Computing Products
Digital and
Consumer Products
Standard Products
AC-DC / DC-DC converters
Linear regulators
PWM controllers                        
LDO                                        
VCore
Controllers
Gate Drivers                        
DDR Memory Controllers
Low / Medium Voltage
MOSFETS
Filters / Protection
Audio Amps                           
DC-DC converters
Analog switches
LED drivers
ESD protection                             
ECL Clocks
Small signal transistors
Standard logic ICs
Small signal diodes
$427
$349
$174
$500
Revenue:
Revenue:
Revenue:
Revenue:
Note: Product Revenues represent last twelve months ending September 2007.


11
AMI Market Segments
Automotive
Industrial
Medical
Communications
Military and Aerospace
Revenue: $169M
Revenue: $157M
Revenue: $104M
Revenue: $48M
Revenue: $48M
In-Vehicle Sensors
Stability Control
Engine Management
Drive by Wire
Headlight Control
Factory Automation
Industrial Networking
Wireless Security
Energy Metering
Medical Imaging
Audiology
Implantable Devices
Diagnostic Therapy
Power over Ethernet
Wireless Base Stations
Switches & Routers 
Optical Networking
Cockpit Displays
Guidance Systems
Infrared Imaging
Applications:
Applications:
Applications:
Applications:
Applications:
Note: Revenues represent last twelve months ending September 2007.


12
Pro Forma Combined Revenue:
$410MM
(2)
Bolster
Existing
End
Markets
-
Automotive
Applications
Applications
Communications
Electromagnetic Mirrors
and Glass
Infotainment
Instrumentation
Stability & Suspension
Lighting
Collision Avoidance
Engine Control
USB
Electronic Transmission
Antilock Braking
Safety Airbag
Traction Control
Security
Active Noise
Cancellation
Multi-zone Climate
Control
Auto Toll Payment
Compass
LED Brake Lights
Backup Sensor
Power Window Sensor
Angular Acceleration
Sensors
Seat Position & Seat
Heating
Steering Wheel Sensors
Transmission Control &
Gearbox Position Sense
Brake Pressure
Tire Pressure Monitor
Engine Control
Headlights
Smart Fusebox
Rain Sensor
Dashboard Electronics
Keyless Entry
Customers
Revenue: $241MM
(1)
(1)
(1)
Revenue: $169MM
(1)
(1)
(1)
(1) Revenues represent last twelve months ending September 2007.
(2) Represents combined financials as reported for the last twelve months ending September 2007 for ON Semiconductor and AMI Semiconductor.
Customers


13
Customers
Customers
Applications
Military Radios / Battlefield
Communications
Cockpit Displays
Guidance Systems
Munitions / Missile Systems
Night Vision
Applications
LTM Revenues of $104MM
(1)
~70 Customers Including Top 7 Medical Companies
Leadership Position with 10% Market Share
(2)
LTM
revenues
of
$48MM
(1)
Ranked
#3
with
8%
Market
Share
(3)
New Market Opportunities
(2) Based on Company estimates and Gartner data for 2006.
(3) Based on Gartner data for 2006 Military / Aerospace ASIC market share.
Military / Aerospace
Medical
Hearing Aids
Neurological Stimulus
Management
Cardiovascular Management /
Pacemakers
Body Temperature Sensing
Blood Glucose Monitoring
CT Scan
Ultrasound
Portable X-ray
Pulse Oximeters
Blood Oxygen/Chemistry
Monitoring
(1) Revenues represent last twelve months as of September 29, 2007.
Implantable Defibrillators
External Portable
Defibrillators
Cochlear Implants
ECG Monitoring


14
Broad and Deep Customer Relationships


15
Leverage ON’s Operational Excellence
Highlights:
Semiconductor International named “Top Fab of 2002”
Quality Magazine named “Quality Plant of the Year 2005
Honoree”
Mil/Aero
certifications
&
NSA
“Trusted
Fab
Status”
(Q4’05)
Best-in-Class Prototype & Production Cycle Times
Hi-Tech Yield & Failure Analysis Equipment & Systems
Future Technology potential with 90nm/65nm capable
Research & Development tool set
Gresham Fabrication Facility
Achieve Operational Synergies
Extend AMI’s
High Voltage and Low Power Offerings
Accelerate Margin Growth


16
Leshan, China
Aizu, Japan
Gresham, OR
Phoenix, AZ
Roznov, Czech Republic
Pietsany, Slovakia
Seremban, Malaysia
(Site 1 & 2)
Carmona, Philippines
Oudenaarde, Belgium
Pocatello, Idaho
Key Locations
Global Manufacturing Infrastructure
Back-end Facilities:
Leshan, China
Seremban, Malaysia (Site-1)
Carmona, Philippines
Wafer Facilities:
Roznov, Czech Republic
Front-end Facilities:
Phoenix, Arizona
Gresham, Oregon
Aizu, Japan
Pietany, Slovakia
Seremban, Malaysia (Site-2)
Roznov, Czech Republic
Legend
Front-end Facilities:
Pocatello, Idaho
Oudenaarde, Belgium
Back-end Facilities:
Calamba, Philippines
Calamba, Philippines


17
Financial Overview
ON
(1,2)
AMIS
(1,2)
Combined
(3)
Last Twelve Months
$522
$134
$388
EBITDA
Employees
Operating Margin
Gross Margin
Revenue
14,675
2,984
11,691
17.4%
13.6%
18.9%
40.0%
44.5%
38.2%
$2,179
$619
$1,560
($MM)
Large revenue base with over $2 billion in LTM revenue
Strong combined gross and operating margins
Significant cash flow generation
(1) Revenues represent last twelve months ending September 2007 for ON Semiconductor and AMI Semiconductor.
(2) Non-GAAP Operating Margin excludes amortization of acquisition and related intangibles and restructuring and impairment charges.
(3) Represents combined financials as reported for the last twelve months ending September 2007 for ON Semiconductor and AMI Semiconductor.


18
Significant Revenue Scale
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor.
** As of 12/31/2006.
/
*
($ in millions)
Combined Company Generates Economies of Scale and
Improved Financial Performance
**
$2,739
$2,546
$2,362
$2,179
$1,857
$1,657
$1,560
$1,316
$1,072
$725
$9,741
$10,923
$13,742


19
Generating Substantial EBITDA
(Excludes Synergies)
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor.
** As of 12/31/2006.
/
*
($ in millions)
Note: Excludes one time items.
**
$2,116
$1,352
$761
$615
$565
$522
$458
$388
$273
$234
$177
$4,435


20
And Significant Free Cash Flow
Free Cash Flow Yield (FCF/ Market Capitalization):
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor
divided
by
the
combined market capitalization.
** Represents
annualized
combined
financials
as
reported
for
the
last
three
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor
divided
by
the combined market capitalization.
*** As of 12/31/2006.
/
*
Market capitalization as of December 12, 2007
***
/
**
(3Q annualized)
8.9%
8.7%
8.4%
7.8%
7.5%
7.0%
6.5%
6.3%
6.3%
6.2%
3.4%
1.7%
NM


21
Transaction Rationale
Accelerates ON’s
Analog
Transformation
Expands mixed signal design and product capability
Over 88% of AMI’s
custom products / design wins are sole sourced
Higher margin product portfolio with products that have long product
cycles
Pro Forma LTM gross margins of 40%
Strengthen End
Market Presence and
Gain Entry into
New Markets
Expands presence in automotive, consumer, communications and
industrial end markets
Gain entry into high growth, higher margin medical market and high-
margin Mil/Aero market
Increase value proposition to end customers with both leading standard
and custom products
Leverage ON’s
Operational
Excellence to Drive
Cost Savings
Successful
track
record
of
cost
reduction
and
rationalization
to
improve
profitability of combined business
Utilize advanced sub-micron Gresham fabrication facility to drive cost
savings and extend product roadmap
Consolidate combined company’s manufacturing network
Significant Scale
and Cash Flow
Generation
Pro Forma LTM revenues of $2.2 billion*
Pro Forma LTM EBITDA of $522 million* (with zero synergies)
Pro Forma LTM free cash flow of $248 million*
Potential to accelerate revenue growth of combined companies
Accretive to earnings per share exiting 2008*
* Represents
combined
financials
as
reported
for
the
last
twelve
months
ending
September
2007
for
ON
Semiconductor
and
AMI
Semiconductor.
Free
cash
flow
defined
as
operating
cash
flow
less
capital
expenditures.
Earnings
per
share
excludes
amortization
of
intangibles