Productivity/Performance Specifications OverviewDr. Vallabh H. DhudshiaQ&R ConsultantStandards Technology Groupvemail@example.com SEMICON West 2006 STEPMethods to Measure/Improve Equipment Productivity
NA Metrics Committee Charter To explore, evaluate, discuss, and formulate 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 manufacturing equipment and materials to enhance the manufacturing capability of the semiconductor and related industries. Its scope includes liaison with other technical committees for the development of metrics-related standards. Its scope is limited to exploring and developing standards and associated training that pertain to common criteria, guidelines, methods, or approaches to be used as the basis for comparative performance measurements of equipment, materials, components, or manufacturing operations.
Metrics Committee Specifications / Standards SEMI E10 SEMI E79 SEMI E35 SEMI E58 (co-owned with I&C Committee) SEMI E116 (co-owned with I&CCommittee) SEMI E124
To Understand SEMI Standards Need to Understand (RAMP): Reliability Availability Maintainability Productivity
What is Reliability? • One of the important equipment characteristics • Longevity measure of failure-free operation interval • Probability of performing intended functions for a specified time under the stated operational conditions
Commonly used in the SC manufacturing industry Categories of Reliability Metrics Reliability metrics can be divided into four main categories: 1. Metrics based on probabilities 2. Metrics based on mean life 3. Metrics normalized by life units 4. Metrics expressed in percentages
What is Maintainability? • Maintainability deals with the time it takes to restore the equipment operations after it stops performing its intended functions. • Maintainability is the probability that the equipment will be restored to a specific operational condition (able to perform its intended functions) within a specified period of time, when the maintenance is performed by personnel having specified skill levels and using prescribed procedures, resources, and tools. • Maintenance can be either unscheduled or scheduled. • The most commonly used maintainability metric is Mean Time to Repair (MTTR). Notes: According to SEMI E10, Repair Time is sum of downtimes for diagnosis, corrective action, equipment test, and verification runs.
What is Availability? Availability is a joint measure of reliability and maintainability. It is defined as the probability that the equipment will be in a condition to perform its intended functions when required.
Availability • Availability = Uptime / (Uptime + Downtime) Where Downtime includes Unscheduled and Scheduled (Preventive Maintenance) downtimes • One of the most widely used parameters of the availability is % Uptime, which is defined as % Uptime = Availability x 100 • Three variations in the availability calculations are defined in SEMI E10.
What is Productivity? Productivity as implied in SEMI E79: Good units Production Rate in relation to the theoretical (available) capacity Widely Used Metric: Overall Equipment Efficiency (OEE)
Hierarchy of Equipment Performance Metrics Ref: “Hi-Tech Equipment Reliability” by Dr. Vallabh H. Dhudshia
SEMI E10 is a Semiconductor Equipment & Materials International (SEMI) Specification for Definition and Measurement of Equipment Reliability, Availability, and Maintainability (RAM). What is SEMI E10? • Developed by a task force under the SEMI Metrics Committee. • First issued in 1986, and revised in 1990, 1992, 1996, 1999, 2001 and 2004 (SEMI E10-0304E).
SEMI E10: Underlying Assumptions & Scope • Underlying Assumptions: • Repairable System • Interval between two successive failures follows Exponential Distribution • Scope: • Non-Cluster tool (entire equipment or • subsystem level) • Single Path Cluster tool • Multi-Path Cluster tool at subsystem level
Key Definitions of SEMI E10 Failure:Any unscheduled downtime event that changes the equipment to a condition where it cannot perform its intended function. Any part failure, software or process recipe problem, facility or utility supply malfunction, or human error could cause the failure. Equipment-Related Failure:Any unplanned event that changes the equipment to a condition where it cannot perform its intended function solely caused by the equipment.
PT PT MTBFP = E-MTBFp = N NE SEMI E10 Reliability Metrics Total Equipment Cycles Total Equipment Cycles MCBF = E-MCBF = N NE E-MCBF = Mean Cycles Between Equipment-Related Failures E-MTBFP = Mean Productive Time Between Equipment-Related Failures MCBF = Mean Cycles Between Failures MTBFP = Mean Productive Time Between Failures N = Number of Total Failures NE = Number of Total Equipment-Related Failures PT = Productive Time
SEMI E10 Maintainability Metrics Total Repair Time MTTR = N • Total Repair Time Includes: • Diagnosis Time • Corrective Action Time • Equipment Test and Verification Time • Repair Time does not include maintenance delays.
SEMI E10 Availability Metrics Equipment-Dependent Uptime % = Uptime x 100 (Uptime + Equipment Caused Downtime) Supplier-Dependent Uptime % = Uptime x 100 (Uptime + Equipment and Supplier Caused Downtime) Uptime Operational Uptime % = x 100 Operations Time
SEMI E10 Utilization Metrics Productive Time Operational Utilization % = x 100 Operations Time Productive Time Total Utilization % = x 100 Total Time
Other SEMI E10 Metrics • Multi-path Cluster tool RAM metrics • Confidence limits for reliability metrics • Rate of reliability growth/degradation
SEMI E79 is a SEMI Specification for Definition and Measurement of Equipment Productivity. What is SEMI E79? • Developed by a task force under the SEMI Metrics Committee. • First issued in 1999, and revised in 2000 and 2004 (SEMI E79-0304). • Changed Effectiveness to Efficiency in 2000 revision.
SEMI E79: Underlying Assumptions & Scope • Underlying Assumptions: • Repairable System • Using SEMI E10 RAM terms and definitions • Equipment of the same design have the same theoretical production time per unit • Subjectivity in Determining Theoretical Production Time (THT) • Scope: • Non-Cluster tool • Module Level • Fixed Sequence (Single Path) Cluster tool • Flexible-Sequence (Multi-Path) Cluster tool
SEMI E79 OEE Metrics Individual Process Modules or Fixed-Sequence Cluster Tools Overall Equipment Efficiency (OEE) = (Theoretical Production Time for Effective Units) / (Total Time) = (Availability Efficiency) x (Performance Efficiency) x (Quality Efficiency) The fraction of total time that equipment is producing effective units at theoretically efficient rates. Availability Efficiency = (Equipment Uptime) / (Total Time) The fraction of total time that the equipment is in a condition to perform its intended function.
SEMI E79 OEE Metrics Individual Process Modules or Fixed-Sequence Cluster Tools Performance Efficiency = (Operational Efficiency) x (Rate Efficiency) The fraction of equipment uptime that the equipment is processing actual units at theoretically efficient rates. Operational Efficiency = (Production Time) / (Equipment Uptime) The fraction of equipment uptime that the equipment is processing actual units. Rate Efficiency = (Theoretical Production Time for Actual Units) / (Production Time) The fraction of production time that equipment is processing actual units at theoretically efficient rates. Quality Efficiency = (Theoretical Production Time for Effective Units) /(Theoretical Production Time for Actual Units
Other SEMI E79 Metrics • Multi-Path (Flexible Sequence) Cluster tool OEE • Reference OEE (R-OEE) • Engineering OEE (E-OEE) • Value-Added In-Process OEE (VA-OEE) • Production Equipment Efficiency (PEE) • Demand Equipment Efficiency (DEE) • Intrinsic Equipment Efficiency (IEE)
SEMI E35 is a SEMI Guide to Calculate Cost Of Ownership (COO) Metrics for Semiconductor Manufacturing Equipment. What is SEMI E35? • Developed by a task force under the SEMI Metrics Committee. • First issued in 1995 and last revised in 2005 (SEMI E35-0305).
What is COO? The Cost of Ownership (COO) is the full cost of embedding, operating, and decommissioning a manufacturing equipment in a factory environment that accommodates the required production volume.
Simple and Basic COO Equation (Fc + Rc + Yc) COO per good unit = (L x TP x Y xU) Where: Fc = Fixed costs Rc = Recurring costs Yc = Yield loss costs L = Life of equipment TP = Throughput Y = Composite yield U = Utilization
Examples of COO Elements Fixed Costs: • The fixed costs include amortized portion of purchase price, taxes and duties, transportation costs, installation cost, start-up cost, training cost, and decommission cost. Recurring Costs: • The recurring costs for a piece of equipment are costs for consumables and materials, maintenance, parts, waste disposal, and operators. Yield Loss Costs: • The yield loss costs are those costs associated with lost production units that are directly attributable to equipment performance.
COO Dependencies • Equipment Acquisition Cost • Equipment Utilization • Equipment reliability • Other downtimes • Recurring Cost • Regular operations • Maintenance • Cost of consumables and waste disposal • Production Throughput Rate • Yield Loss (Scrap) Cost • Product yield
SEMI E124 SEMI Provisional Guide for Definition and Calculation of Overall Factory Efficiency (OFE) and Other Associated Factory-Level Productivity Metrics. What is SEMI E124? • Developed by a task force under the SEMI Metrics Committee. • First issued in July 2003, last revised in November 2003 (SEMI E124-1103).
What is OFE? Overall FactoryEfficiency (OFE)shows how well a factory is operating compared to how well it could be operating for the given product mix. OFE = volume efficiency x yieldefficiency Volume Efficiency is a measure of the total efficiency of the process with respect to the factory dynamics. Yield Efficiency is a measure of overall material efficiency.
Provides company-wide and industry-wide common language for terms, definitions, and calculations of SC Manufacturing Equipment performance/productivity metrics. Provides a common framework for clear and accurate communications between IC Makers and their equipment suppliers. Provides a standard for the design of automated RAM data collection system and Equipment Performance Tracking (E58 and E116). Provides structure and hierarchy to equipment performance/productivity metrics. Equipment Purchase Specifications may require that equipment performance/productivity measurements are based on SEMI Standards. Equipment Evaluation Programs (EEP) and Joint Development Programs (JDP) may use SEMI Standards metrics. Why SEMI Standards?