PV Pastes an example for industrial leadership in Europe Heraeus Precious Metals Dr. Michael Jörger, VP R&D

Outline Heraeus, a material supplier in the PV Market PV industry trends Case study – line conductivity How to remain competitive in Europe (PV Pastes) 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Heraeus at a glance Heraeus is a globally active precious metals and technology Group with firm roots in Germany. The company has been family-owned for over 160 years. We operate in global niche markets characterised by lasting growth and attractive returns. 13,300 employees, €4.8 billion product revenue, €21.3 billion precious metals trading revenue Key markets – Precious Metals, Materials and Technologies, Sensors, Dental Products, Biomaterials and Medical Products, Quartz Glass, Specialty Light Sources 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Heraeus and the PV Market Leading supplier of front side metallization pastes Globally present production and R&D sites Collaborator with specialised equipment manufacturers worldwide Partner with European universities and research institutes on technical projects 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Our Core Competences 35 years expertise in R&D and manufacturing thick film pastes In-house R&D facility Own precious metals, glass powder and vehicle production In house precious metals trading department 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Ag * Front side contacts Front side busbars Rear side pads * Back side field 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Market development – PV cell production 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

PV installations Source: EPIA January 2012 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Cost pressure for PV industry 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

PV Pastes and Other Materials Market 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Options for Cost Reduction Higher efficiency Alternative glasses Improved contact resistance Less material Fine line printing Higher density lines Alternative material → Ag-free or Ag-reduced Alternative production methods Seed layer Plating Galvanisation 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

96xx aims for higher eff. and lower paste usage Ph. 3 New Gen. Seed layer Sampled Current product Multi Cell Eff. (%) SOL96XX (better contact) (2012) SOL9455 (Fine Line) SOL9411 (2011) SOL9235H (2010) We can simplify customer’s technical needs into the two: improve eff. and decrease paste usage. Our development follows that trend. To grow out of our current main product SOL9411, we took three different approaches to meet customer’s need. Newly developed Fine line paste SOL9455 which is being scaled up can improve eff. upto 0.1% and save paste up to 10% compared to SOL9411. Low Ag paste 9442 although can save upto 40% of paste, need further improvement on eff. Improve contact is the key driver for FS paste. We are taking multiple approaches to address this challenge, which I will describe in my next few slides. In Hanau we have half scientist take care of developing seed layer for plating process, in which paste usage will be significantly dropped as shown on the chart. FS Ag paste usage (gram/cell) 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Critical improvements over the years: line conductivity (1) Improved line conductivity Sintering Higher silver percentage resulting in denser fingers 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Critical improvements over the years: line conductivity (2) Improved line conductivity Sintering Better line uniformity Improved line uniformity Smaller difference min-max Obtained by improvements in vehicle (binders and solvents) 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Critical improvements over the years: line conductivity (3) Improved line conductivity Sintering Better line uniformity Better aspect ratio and availability of better screens 2009 2010 2011 2012 SOL9117 SOL9235H SOL9411 SOL9600 130µm 100µm 63µm 55µm In the years, screen printing tools and screens have been improved, but the major jump forwards has been made by the paste manufacturers. In 2006, printing a 160 micron line with an average height of 16 to 18 micron was state of the art. By just improving the paste quality, it is possible now to make higher lines with have the width, resulting in a finger with comparable conductivity, but which only have the surface area covered. By using print on print, which is possible due the precision of the newest hardware with an accuracy of only 10 micron, lines of less than 70 micron with a height of over 40 micron can be obtained. This means that you could either chose to reduce the percentage of the wafer covered by metal, or by placing more fingers on the wafer and keep the same percentage metal coverage and facilitate an even higher sheet resistance 52µm 63µm 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

How to remain competitive in Europe Close interdisciplinary collaboration with research institutes and entire industry value chain, from powder to solar cell module Maintain leading edge in material & process development Strong equipment and manufacturing base in Europe Strict intellectual property protection Guarantee material supply chain, strengthen security of supply of raw materials Highly educated workforce Guarantee innovation friendly environment!!! 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus

Thank you for your attention! Dr. Michael B. Jörger Vice President R&D Thick Film Division Heraeus Precious Metals GmbH & Co. KG Heraeusstr. 12-14 63450 Hanau Germany Tel: +49-6181-35-4779 Email: michael.joerger@heraeus.com 20 June 2012, Industrial Technologies 2012, Dr. Joerger, Heraeus