2005 September Newsletter

Volume 1, Issue 6

September 2005

Welcome to the Semitracks Online Monthly Newsletter! It is our goal that you find this newsletter interesting, informative and useful. Please email any comments or feedback to This email address is being protected from spambots. You need JavaScript enabled to view it. .

1. Failure and Yield Analysis Short Course

Presenter - Christopher L. Henderson

September 19-22 at the Embassy Suites - Santa Clara

October 17-20 at the Hilton Singapore

Semitracks offers the most comprehensive course on Failure and Yield Analysis on the market. We have updated this popular short course substantially over the past year. The course includes our 800-page manual and CD-ROM. This year, we are offering the course at the Hilton Singapore as well as in Santa Clara. To register for either of these events, click here.

2. Upcoming Conferences

International Symposium for Testing and Failure Analysis

November 6-10,2005 San Jose McEnery Convention Center in San Jose, CA

We will be located in Booth #315.

International Reliability Physics Symposium

March 26-30, 2006 San Jose McEnery Convention Center in San Jose, CA

To view the IRPS website, click here.

3. Course Schedule

Invest in yourself and your staff. Time is running short to enroll in our Fall courses on Semiconductor Reliability, Failure and Yield Analysis, and Process Integration. Come and learn from the experts!

Process Integration

Process Integration is becoming more challenging with each technology node. The fortunes of your company may depend on how successfully you and your team can integrate disparate processing steps into a single, optimized flow. Lily Springer, our expert in Process Integration and Mixed Signal Design, guides you through the critical and challenging aspects of this topic. She covers both digital and analog issues related to process integration. Let your colleagues know!!

Semiconductor Process Integration (December 6-8) – Embassy Suites - Santa Clara, California

Failure and Yield Analysis

Are you new to failure analysis? Does your position require you to have an understanding of failure analysis? Learn about the latest techniques for analyzing complex devices. We have the most comprehensive short course in the industry covering failure analysis. We cover all the techniques from the simple ones (such as Liquid Crystal) all the way to complex ones (such as PICA and Laser Voltage Probing). Learn the secrets of analyzing a component right every time.

Failure and Yield Analysis (October 17-20) – Hilton Singapore - Singapore

Failure and Yield Analysis (September 19-22) – Embassy Suites - Santa Clara, California


Reliability is a critical element to the success of any semiconductor product. Reliability margins are increasingly squeezed by today’s deep submicron technologies. Learn about the major reliability failure mechanisms, test structures, and test equipment. Learn how to optimize reliability, performance, and cost.

Semiconductor Reliability (September 26-28) – Embassy Suites - Santa Clara, California

Packaging Design

This course provides an overview of the packaging design process. The course covers current packaging technologies, including chip scale packaging, Ball Grid Array technology and other current concepts. This class focuses on techniques and the importance of thermal and mechanical simulations. Discussions and examples will concentrate on thermal performance simulations, assembly & packaging stresses, package reliability (including solder joint fatigue simulation), and interactions between chip and package. In addition, a special section will be examples of successful wafer level simulations.

Packaging Design (October 12-14) - Santa Clara, California

To register for our courses, register online or download the registration form. Fax completed form to Semitracks at (505) 858-9813, or call (505) 858-0454 to register by phone.

We offer other courses as well as in-house courses. For more information, visit our website at http://www.semitracks.com.

4. Semitracks Segment of the Month

Semitracks’ new and improved online training is convenient, up-to-date, and cost effective. Access the same material presented in our courses whenever you need it, right when you need it without having to worry about the high costs and hassle of traveling. The semiconductor field is an ever-changing one. With access to the most current information, you can stay on top of the new technology. Online training is also very cost effective. For only $500 per year, you gain access to thousands of dollars worth of courses and course material.

Give our online training a try – for free. This month’s topic is an overview of Analytical Characterization Techniques. There are a wide variety of analytical techniques used to characterize the surface of a semiconductor device. These range from techniques like GDMS, which are sensitive to surface contamination, to SIMS, which allow accurate depth profiling of implanted species. To learn more, click here.

Sign up to access all of Semitracks online training at http://www.semitracks.com/default.htm and “Learn from the Experts” when it’s convenient for you.

5. Technical Tidbits

Thermal Resistance

The thermal resistance R sub sigma is related to the thermal conductivity of the heat sink by the equation shown here, where t is the thickness of the heat sink, k is the thermal conductivity, and A is the cross sectional area normal to the heat flow direction. The subscript JS refer to heat transfer from the junction to the heat sink. Although a component of the heat flow will be mostly normal to the surface, there is heat spreading that occurs when the heat sink is bigger than the junction. This means that one must perform thermal modeling to gain a more accurate picture of the heat transfer. If there is more than one material acting as a heat sink, the thermal resistance can be modeled as a sum of the individual thermal resistances and thicknesses of each of the layers according to the equation shown here.

Although the equations shown on the previous slide can model a stack where no spreading occurs, most power semiconductor packaging schemes use a heat spreader. The structure might look like the one shown here. In order to accurately model the thermal transfer, one must introduce the concept of an interfacial heat transfer coefficient which controls the degree of heat spreading. The heat spreader can be treated as a radial fin structure. When one solves the heat transfer equation for the radial fin and adds the single dimension for heat flow, one can get a more accurate estimation of the overall thermal resistance. Here, R sub sigma three is the thermal resistance of the fin, R sub sigma one represents the thermal resistance of the chip stack, R sub sigma four represents the thermal resistance of the heat spreader directly below the stack, and R sub sigma two represents the thermal resistance of the heat spreader away from the stack. The overall thermal resistance can then be modeled by the equation shown here at the bottom. More accurate modeling can be performed by computer to evaluate more accurate thermal resistance models that involve Bessel functions.

6. Our Mission

Education and Training for the Electronics Industry

Semitracks provides education, training, and certification services and products for the electronics industry. We specialize in serving Semiconductor, Microsystems and Nanotechnology suppliers and users. Semitracks Inc. helps engineers, technicians, scientists, and management understand these dynamic fields. We offer courses in Semiconductor Reliability, Test, Packaging, Process Integration, Failure and Yield Analysis, and Focused Ion Beam technology. Learn from the Experts.