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 AMIS employees on December 17, 2007 regarding ON’s business.


1
The Power of
ON Semiconductor
About ON Semiconductor
December 2007


2
Safe Harbor Statement and 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.
425 Language


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
Safe Harbor Statement and 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.”


6
President and
Chief Executive Officer
Keith Jackson
MANUFACTURING
SERVICES
Bill George
STANDARD PRODUCTS
Bill Hall
LEGAL
Sonny Cave
HUMAN RESOURCES
Colleen McKeown
COMPUTING PRODUCTS
Bill Schromm
AUTOMOTIVE AND POWER
REGULATION  PRODUCTS
Andy Williams
SALES AND MARKETING
Bob Mahoney
CHIEF OPERATING OFFICER
John Nelson
FINANCE
Donald Colvin
DIGITAL AND
CONSUMER PRODUCTS
Manor Narayanan


7
From the Socket to
the Pocket™
ON Semiconductor is
aligning its resources to
become the leading
supplier of premier power
solutions worldwide.


8
3Q07 Revenues: $402.9Million
Leading supplier of both power analog and power discrete components
Significant portfolio breadth
Global penetration of key applications and regions
Leveraging capabilities in low cost manufacturing
More 2 billion products shipped monthly


9
Segment and Regional Profile


10
Worldwide Presence


11


12


13
Product and Technology
Progress
Significant new products
AC-DC and DC-DC converters and controllers
for power efficiency
Dual-edge VRM power controllers
Class D Audio Amplifiers for high-fidelity sound
LED Drivers for flash and LCD backlighting
Drivers and Pre-Drivers for automotive electric
motors
Protection devices for a wide range of electrical
transients
MOSFETs, diodes, and transistors in
micro-packages
Significant progress on critical
technologies
VHVIC3
PS5LV
Trench


14
Power Supplies
Power Efficiency Leadership
Solutions for all power supply efficiency areas
Active mode –
save power when devices are consuming the most
energy
Standby mode –
save power when devices are idle (most of the time)
Power factor correction –
enhance the efficiency of the electric grid
GreenPoint™
family of efficient power supply solutions
80 PLUS®
compliant ATX  -
2005
CRT and LCD TV power supplies –
2006
Notebook and monitor power adapters -
2006
Printer and game console power adapters -
2007


15
Portable Consumer
Protection for
Audio Lines,
Keypads, and
Battery Charging
Audio Subsystems
Filtering for
Camera
Interface  and
LCD Interface
Display and Flash
LED Lighting
Battery Charging
Control
Data Switching


16
Automotive
Powertrain
Exterior Lighting
Safety &
Chassis
Driver Information &
Telematics
Interior Lighting
Audio &
Infotainment
Body


17
Computing
Core Power
Chipset Power
DDR Power
For Notebooks, Desktops, Game Boxes, Displays, Adapters
Multi-Phase Controllers
DC-DC Switching Regulators
MOSFET Drivers
AC-DC Conversion
Battery Chargers
Linear/LDO Regulators
LED Drivers
Voltage Supervisors


18
ON Semiconductor is ideally situated to be the
preferred power management solutions supplier:
We have the necessary system knowledge to meet tomorrow’s
power management challenges;
We have the analog and power IC design expertise to translate
our understanding into real products;
We have the broad portfolio to offer both parts and system
solutions;
We have the manufacturing capability to deliver them at the right
value point;
We have the supply chain management expertise to ensure you
get your parts when you want them, where you want them, and
how you want them.
Conclusion


19
The Culture of ON Semiconductor


20
ON Semiconductor Mission and Vision
ON Semiconductor Mission and Vision
Vision
Vision
ON Semiconductor
is dedicated to becoming the premier
supplier of performance power solutions
worldwide.
Mission Statement
Mission Statement
To provide our customers with high
quality, cost effective solutions to solve the
demanding power management and circuit
protection design challenges.


21
Respect
Integrity
Initiative
The Center of Our Success


22


23
Product
Leadership
Customer
Intimacy
Supply Chain
Manufacturing
Customer Service
Sales
Sales and Applications
Product Marketing
Customer Service
Product Marketing
Design
Technology
Applications
Operational
Excellence
(Lowest Cost Producer)
Organizational Leadership and Roles


24


25
ON Semiconductor is dedicated to the recognition and reward for the contributions
provided
by
our
technical
community.
ON
Semiconductor
views
its
technical
talent
as
a
key differentiator for the successful implementation of ON Semiconductor’s Vision
statement.
Recognition Program Categories
Technical Ladder
Patents
Technical Publications
Innovative Product Awards
Engineering Excellence Awards
Technical Recognition Overview
Innovative
Products
Awards
Engineering
Excellence
Awards
Technical
Recognition
Technical
Ladder
Career
Path
Patents
Technical
Publications


26
The Technical Ladder is a career progression path for the advancement of
technical contributors at ON Semiconductor. It provides equivalent
compensation and structure to the managerial advancement path.
The Technical Ladder is a path of opportunity for technical contributors
and technical managers at ON Semiconductor.
The Technical Ladder recognizes and rewards technical contributors
globally.
The Technical Recognition Council oversees the Technical Ladder
program.
Technical Ladder Career Path


27
A technical contributor is a person whose primary function is to
contribute to the corporation by providing technical expertise in a
specific area of knowledge in an engineering discipline.
A technical contributor may or may not have reports.
Some examples of technical contributors include:
Engineers
Process
Design 
Manufacturing and Test
Product and Quality
Field application engineers
Scientists
Technical Contributor


28