PV Standards – A comprehensive overview of activities for SEMI PV Group
In March of 2007, at the PV Fab Managers’ Forum in Leipzig, Germany, industry leaders gathered to focus on issues and concerns affecting overall manufacturing costs in the PV industry. It was agreed that, in order to reduce costs associated with the manufacture of photovoltaic cells, panels, and modules, standards would be required. Although SEMI had been active in developing PV Standards since 1981, these activities had traditionally taken place in the Silicon Wafer Technical Committee. Given the urgency and importance of PV Standards, however, the need for a committee dedicated to PV manufacturing was clear.
The European Regional Standards Committee endorsed the petition to create the new committee, and formation of the SEMI Photovoltaic Standards Technical Committee (TC) was formally proposed to the SEMI International Standards Committee (ISC) at SEMICON West, on July 19, 2007. Dr. Winfried Hoffmann, CTO Solar Business Group, Applied Materials, and European Photovoltaic Industry Association (EPIA) President, presented the petition to form a joint SEMI-EPIA Standards Committee in Europe to the ISC. Dr. Hoffmann stated that EPIA had expressed its interest to use the SEMI Standards platform to look for consensus on product issues, and although SEMI Standards are manufacturing needs oriented, that this extension was still relevant to SEMI, because manufacturing standards often depend on product and materials standards.
ISC approval of the petition launched the start of activities in Europe, followed by formation of the North American TC later in December of 2007. In addition, a PV Working Group (WG) was formed in Taiwan in 2008, and all signs point to Japan seeking approval of a TC in 2009.
- To explore, evaluate, discuss, and create consensus-based standard measurement methods, specifications, guidelines, and practices that, through voluntary compliance, will promote mutual understanding and improved communication between users and suppliers of photovoltaic manufacturing equipment, materials and services to enhance the manufacturing efficiency and capability so as to reduce manufacturing cost of the photovoltaic (PV) industry.
- To include liaisons and synergies with other SEMI technical committees for the development of PV-related standards. The PV standards committee scope is limited to exploring and developing standards that pertain to common criteria, guidelines, methods for control and comparison of PV-related process / metrology equipment, materials, components, or manufacturing operations. It will seek to support the international need for increasing PV product / process yield and reducing related PV costs per Watt peak.
- In anticipation of SEMI’s ANSI accreditation, this committee will investigate opportunities towards ISO/IEC harmonization of efforts. In addition to the above, the committee will also facilitate any industry initiatives towards product standardization needs.
The first European PV TC meeting was held on September, 2007, in Milan, Italy. At this meeting the Photovoltaic Equipment Interface Specification (PV-EIS) TF was approved and a decision was made to launch a SEMI-EPIA needs assessment survey. This survey proved to be instrumental in identifying standardization topics as well as identifying individuals from the PV industry interested in developing standards. The PV-EIS TF balloted a guide for PV equipment communication interfaces (PVECI) in late 2008, which will be reviewed at the upcoming EU PV TC meeting on March 10, 2009 in Dresden, Germany.
At the EU PV TC meeting on September 7, 2008, in Valencia, Spain, a new TF was approved to perform regular 5-year updates of SEMI M16, Specification for Polycrystalline Silicon, to keep up with technical developments in the field.
Dr. Laszlo Fabry, Senior Scientist, Business Division Polysilicon, Wacker Chemie AG
- Extensive SEMI Standards experience since 1988
- Silicon Wafer, Liquid Chemicals and Gases
- Previous TF leader for SEMI M33 (PV Wafer) Std
- Earlier long-time Head of Corporate Analytical Services, Siltronic AG
Dr. Hubert Aulich. PV Crystalox Solar plc.
- Initiated several initiatives as board member of EPIA to stimulate standards for PV in Europe and beyond
- Dr. Aulich started at Siemens 1974 in PV, and is currently Exec. Director of the German operations of PV Crystalox Solar
Photovoltaic Equipment Interface Specification TF
The TF is chartered to develop of a suite of standards to specify and define a unified equipment communication interface for photovoltaic production systems. Currently, there is no unified equipment communication interface available for the photovoltaic industry. Several proprietary solutions are being developed and used in actual manufacturing lines. A common standard will provide a strong contribution to cost reduction, reduce ramp-up time and allow for access to equipment and process data.
- To evaluate the usage models (use cases) of known clients of the interface and identify key expectations of those clients.
- To evaluate existing PV solutions as well as existing industry standards (SEMI and others) which are applicable to the problem and identify gaps or synergies.
- To evaluate options - extend existing industry standards and SEMI standards in particular.
- To define a framework for this interface and a related standards development roadmap.
- To select technologies which best support the goals of PV equipment communication.
To define the representation of data accessed via the interface
(read - functionality).
- To define mechanisms for advanced equipment and process control (command - functionality).
- To provide implementation directive (mappings, bindings) - Result will be mapped to industry-standard software technologies.
- To define what this interface does NOT cover.
- To define and specify test methods and test criteria to fulfill PV equipment interface standard compliance.
M16 Revision TF
Established September 2008
The TF is chartered to perform regular five-year update of M16-1103: Specification for Polycrystalline Silicon. The updated M16 will include all available types of bulk polysilicon products which are manufactured by thermal gas phase deposition, and facilitate their manufacturing according to specification. Feedstock purchasing and sales procedures will also be simplified on the semiconductor and solar marketplace. The scope will also be expanded to novel products such as solar poly, and updates of Terminology and Test Methods will also be covered.
The first North America Photovoltaic Committee meeting was held in San Diego, California on October 31, 2007. The meeting had excellent attendance, as awareness of the need for PV Standards to reduce manufacturing cost and improve communication between suppliers and users was at an all-time high. Since that initial meeting, five TFs have been formed, and over 300 people worldwide are registered for the SEMI PV TC.
Dr. Heiko Moritz, President of Caerus Systems
- Vice President of Sales and Marketing at GT Solar Technologies
- 18 years of experience in research, product design, and sales and marketing in the semiconductor, vacuum and photovoltaic industry
- Ph.D. in Physics from the Research Center Juelich, Germany
Win Baylies, Founder and President of BayTech Group
- Vice President of ADE Corporation, 1974-1990
- Specialist in semiconductor, flat panel display, and photovoltaic
- 20+ years of management experience in the Electronics industry. Author of numerous technical articles, test methods, international round robin tests and related research reports.
International PV Analytical Test Methods TF
Established October 2007
This TF was chartered to develop standards for analytical test methods for the international photovoltaic industry. The TF’s initial focus is on two test methods required by industry: Glow Discharge Mass Spectrometry (GDMS) and Inductively-Coupled-Plasma Mass Spectrometry (ICP-MS) as applied to impurities in silicon feedstock for multicrystalline silicon PV. The TF recently balloted a Test Method for Measuring Trace Elements in Photovoltaic-Grade Silicon by High-Mass Resolution Glow Discharge Mass Spectrometry, which was approved and published as SEMI PV1-0309.
The TF is now working on their next document, Test Method for the Measurement of Elemental Impurity Concentrations in Silicon Feedstock by Bulk Digestion, Inductively-Coupled-Plasma Mass Spectrometry. This document is expected to go out for ballot later this year.
Future work will include analytical techniques for solid materials will be considered as appropriate for application to both thin-film PV and bulk PV, Si and non-Si, as follows:
- Auger Electron Spectroscopy (AES)
- Energy Dispersive X-ray Spectroscopy (EDS)
- Fourier Transform Infrared Spectroscopy (FTIR)
- Hydrogen Forward Scattering Spectrometry (HFS)
- Low Energy X-ray Emission Spectrometry (LEXES)
- Particle Induced X-ray Emission (PIXIE)
- Raman Spectroscopy (Raman)
- Rutherford Backscattering Spectroscopy (RBS)
- Scanning Electron Microscopy (SEM)
- Secondary Ion Mass Spectrometry (SIMS)
- Scanning Probe Microscopy (SPM)
- Transmission Electron Microscopy (TEM)
- Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)
- Total Reflection X-ray Fluorescence (TXRF)
- X-ray Photoelectron Spectroscopy (XPS)
- X-ray Diffraction (XRD)
- X-ray Reflectivity (XRR)
PV Carrier Task Force
Established April 2008
The PV Carrier TF was chartered to develop standards for carriers for the international photovoltaic industry. Its scope encompasses carriers for use with PV wafers, substrates, cells, and modules that are used in transferring, shipping, equipment automation, and buffer storage. The TF is currently recruiting users, suppliers, and others such as Fraunhofer, Q-Cells, Adept, Applied Materials, and Entegris. Once the core group is established, the TF will start work on drafting a Specification for 150 mm, 156mm, and 200mm Wafer and Cell Transfer Carriers for Use in PV Manufacturing. Broad participation from the PV industry is highly encouraged for this activity.
PV Electrical Properties Measurements TF
Established December 2008
This TF’s charter is to develop standards or practices for non-destructive electrical properties measurements for the photovoltaic industry. The TF will adapt existing SEMI and ASTM Test Methods and Practices for non-destructive and mercury probe measurement of the sheet conductance, sheet resistance, mobility, dopant density of the substrates and thin film depositions for research and development and for process control of production.
PV Facilities TF
Established October 2008
To leverage as much as possible of the existing SEMI Standards portfolio, the TF is now assessing about 130 of the nearly 800 current SEMI standards as to their applicability to PV manufacturing, regardless of whether the facilities are common to known manufacturing technologies or unique to specific methodologies. The PV-FAC TF will be documenting utility lists, process flows, facilities features, and other characteristics during the assessment.
The TF will develop a Prioritization Matrix, including numerical ranking (1-2-3, high-medium-low), of the SEMI Standards assessed in order to determine:
- Applicability of the SEMI Standard to PV
- Ease of transition from semiconductor to PV
- Urgency to PV industry
- Cost-effective potential
- Environmental, Health Safety (EHS) and/or IP (Intellectual Property) Implications.
These priorities will be compared to and matched with the results from the SEMI PV Group-EPIA
PV Standards Needs Assessment Survey (February 2008), and will support the efforts of the PV Standards Roadmap Core Team (see below) currently in progress.
PV Gases and Chemicals Purity Task Force
Established July 2008
Chemicals specifications for semiconductor grade have been around for years, but PV is a whole new and different field. There are no known accepted standards within this area. Thus, the TF was formed with the intent to provide written documents for gases and chemicals that can be used to obtain consistent and specified process materials for use in the PV industry.
The TF will shortly be deploying surveys on chemicals, gases, and water specifications being used in the PV industry. Relevant gases include Oxygen, Hydrogen, Nitrogen, Argon and Silane. For liquid chemicals, the list is expanded to KOH, NaOH, H3PO4, H2SO4, NH4OH, H2O2, HF, HNO3, and HCl. A separate water questionnaire is being discussed and finalized.
Shortly after SEMI PV Standards activities were initiated in Europe and North America in 2007, a PV Standards Working Group (WG) was formed in Taiwan. (A WG can issue proposals for Standards, but these must be approved by an existing TC before they go to ballot) The Taiwan WG’s kickoff meeting was held on May 9th, 2008 at Taiwan’s Industrial Technology Research Institute (ITRI), with over 40 companies and 70 leaders from the PV industry gathering to discuss how to catch up with activities in other regions and to brainstorm on Taiwan’s needs in PV standards.
Today, the Taiwan WG contains multiple sub-WGs, covering areas such as silicon feedstock, equipment interfaces, and cell performance. The WG and its sub-WGs have met over 20 times to date, gradually consolidating the industry’s needs into concrete standards proposals. In order to avoid duplicating the efforts of other regions, the WG has decided to focus on wafer/cell appearance, simulator equipment standards and reference module standards.
As the Taiwan PV industry, measured by volume, is ranked fourth in the world, industry leaders are eagerly anticipating the development of SEMI PV Standards, which will ensure the growth of the industry. In addition to working on standards development, the Taiwan PV WG looks forward to collaborating with other regions, and also hosting workshops to educate local industry on SEMI Standards.
Global PV Standards Roadmap
In May 2008, PV Group established a Core Team of volunteer experts representing equipment and materials manufacturers, cell makers, third parties and other special interests. The Core Team agreed to support the development of a global Standards Roadmap for photovoltaic (PV) manufacturing processes, from feedstock materials to finished cells and modules, with the goal of presenting a comprehensive PV Standards Roadmap by July 2009.
In February of 2009, the Core Team issued a PV Standards Guidance Document, which identifies over 60 categories of existing SEMI Standards and Safety Guidelines that are applicable to PV manufacturing, including over 30 that are immediately applicable with minor revision.
The Core Team is now actively recruiting additional companies involved in PV manufacturing, especially cell and module manufacturers, as well as strengthening ties with other Standards Developing Organizations (SDOs) to maximize available expertise and volunteer resources. The Core Team’s main priority will be to complete the applicability assessment on an individual document basis, and also to initiate efforts in four focus areas with special PV manufacturing requirements: automation, materials & substrates, facilities, and EHS. The next Core Team status report is scheduled for release at SEMICON West in July 2009.
For more information on PV Standards activities at SEMI, please contact:
PV Standards – Europe
Saviour Alfino (firstname.lastname@example.org)
PV Standards – North America
Kevin Nguyen (email@example.com)
PV Standards – Taiwan
Leon Huang (firstname.lastname@example.org)
PV Standards Global Roadmap
Bettina Weiss (email@example.com)