Overview
IEC TS 61994-4-4:2010 is a technical specification developed by the International Electrotechnical Commission (IEC) that provides a comprehensive glossary of terms and definitions related to single crystal wafers used in surface acoustic wave (SAW) devices. As part of the IEC 61994 series for piezoelectric and dielectric devices for frequency control and selection, this document emphasizes the precise terminology necessary for technical communication, specification, and standardization efforts in the field of SAW device materials. This second edition reflects the latest advancements by including new terms, rearrangement in alphabetical order, and appending concepts such as "reduced LN," "reduced LT," and "reduction process."
Key Topics
IEC TS 61994-4-4:2010 covers a range of key topics essential for manufacturers, researchers, and users of SAW device materials:
- Single crystal wafers: Definitions and properties, including materials such as lithium niobate (LN), lithium tantalate (LT), lithium tetraborate (LBO), lanthanum gallium silicate (LGS), and synthetic quartz.
- Material characteristics: Terms include lattice constant, congruent composition, crystal orientation, and reference plane.
- Quality specifications: Acceptable quality level (AQL), fixed quality area (FQA), local thickness variation (LTV), total thickness variation (TTV), and related measurement parameters.
- Physical defects and attributes: Definitions of chips, cracks, dimples, pits, scratches, orange peel effect, warp, sori, and surface roughness.
- Reduction processes: Explanation of "reduced LN" and "reduced LT" materials, including the purpose of the reduction process for SAW wafer properties.
- Crystallographic details: Description of orientation, SAW propagation direction, and relevant cuts (such as ST-cut).
Applications
The terminology defined in IEC TS 61994-4-4:2010 is vital in multiple areas of the electronics and frequency control industry:
- Standardization and Procurement: Enables precise specification and comparison of single crystal wafers for SAW devices.
- Wafer manufacturing: Facilitates consistent quality and process control by providing clear terms for defects, tolerances, and measurements.
- Research and Development: Supports the work of scientists and engineers who design, test, and innovate SAW-based filters, sensors, and frequency control components.
- Technical communication: Assists stakeholders including manufacturers, suppliers, and end users in using standardized language when discussing SAW device materials.
- Quality assurance: Provides the foundational terminology needed for quality inspection, conformance testing, and reporting.
Related Standards
For comprehensive application and compatibility, IEC TS 61994-4-4:2010 references and complements several other key standards:
- IEC 61994-4-1: Glossary - Piezoelectric materials - Synthetic quartz crystal
- IEC 62276: Specifications and measuring methods for single crystal wafers for SAW device applications
- IEC 60410: Sampling plans and procedures for inspection by attributes
- ISO 4287: Geometrical product specifications - Surface texture: Profile method - Terms and surface texture parameters
- IEC 60050-561: International Electrotechnical Vocabulary - Piezoelectric devices for frequency control and selection
By harmonizing terminology for single crystal wafers in SAW devices, IEC TS 61994-4-4:2010 strengthens international communication, supports high-quality manufacturing, and underpins the growth of SAW technology in electronics and telecommunications. This standard is essential for ensuring clarity, consistency, and reliability throughout the SAW material supply chain.