AOI IC (2014) 1. 2. AOI Lecture : TSMC, UMC… : , … Precision Metrology Lab. IC 314 0.3% 1 LCD 111 50% 56 Array/CF/Cell PCB/PCBA 123 52% 64 SMT 33 >80% 40 ( 581 30% 161 IC LCD PCB ) ( ) 3D 0.1µ FPC PS CCL / 2 Precision Metrology Lab. IC manufacturing chain - Front-end System .gds dB System Synthesis, simulation, and physical layout Design Design Reticle Mask Tooling Designing stage Lot/wafer wafer processing Wafer/dice wafer Sorting ( C/P testing) C/P : Circuit probing Front-end Back-end Turnkey Fabless Fundry IDM AOI Lecture Precision Metrology Lab. Precision Metrology Lab. Role play of Metrology Tool in Wafer Processing Wafer Production Flow Mask W/S Diffusion W/O Litho. Etch Thin Film • Measurement AOI Line Width Check---------------CD SEM, SCD Displacement Check-----------Overlay Measur. System Thickness Check ---------------Thin Film Measur. System,Ellipsometer • Inspection Mask/Wafer Defect check ---Micro/Macro/Insp. System AOI Lecture Precision Metrology Lab. Introduction of The AOI Tools in IC FABs -Application & Requirement Name W.J. Liu / UMC AOI Lecture Precision Metrology Lab. Litho. Patterning Flow & ADI Product Pass/Fail Disposition Surface Prep Resist Spin Hard Bake Edge Bead Removal Develop Soft Bake Post Expo. Bake Ali gn and Expose After-Develop Inspection (ADI) Overlay check CD Measure Macro Defect Inspection Micro Defect Inspection Pass Fail Rework AOI Lecture Scrap Precision Metrology Lab. Litho. Production Tools Mask Wafer Hot plate Lens Light source Scanner (US$ 7,000,000) AOI Lecture Wafer transfer Develop unit Coating unit Track (US$ 2,000,000) Precision Metrology Lab. Overlay Measurement System Introduction AOI Lecture Precision Metrology Lab. AA vernier layout on Mask AOI Lecture Precision Metrology Lab. AA vernier layout On Preceding Layer AOI Lecture On Present Layer Precision Metrology Lab. AA Measurement Principle Overlay Offset X Measure the Distance between the Present Layer (Inner) & the Preceding Layer (Outer) AOI Lecture Precision Metrology Lab. AA Measurement Algorithm AOI Lecture Precision Metrology Lab. The Challenge for AA Measurement Case 1. Shallow step height of pre-layer mark caused by STI CMP process Case 2. Rugged Metal surface and the damaged mark AOI Lecture Precision Metrology Lab. Overlay distribution for different temperature of Al Overlay with different deposition temperature of Al (nm) 90 3s-Xmax 3s-Ymax 80 70 60 50 40 30 20 10 0 250C 300C 400C • Sample : 250c: 7cps 300c : 5cps 400c : 7cps • Measure point : 7 points/field, 14 field/wafer • The Overlay of low-temperature Al can be improved over 44% than high temperature (400C) AOI Lecture Precision Metrology Lab. Overlay distribution for different temperature of Al 400C 250C • The grain of 400C Al is larger than low temperature(250C) AOI Lecture Precision Metrology Lab. Requirement for Overlay Measurement Tool Precision for different substrate Repeatability for different substrate Matching between tools Program portability MAM time High Throughput Aligner analysis Real time overlay analysis Good Pattern Recognition AOI Lecture 3nm 3nm 3nm 3nm 2sec Precision Metrology Lab. Critical Dimension Measurement Tool Introduction --- CD SEM Overview AOI Lecture Precision Metrology Lab. Specifications Model Advance Exist Resolution(nm) 3 Vacc(V) 300-1600 3 500-1600 (300V:Option) Throughput(w/h) (5 points/wafer) MAM time(sec) Repeatability (nm:3 ) Stage Accuracy ( m) Pattern Rec. ArF Resist Meas. Charge Correction Func. Process Monitoring AOI Lecture 65 56 <5 2.0(L/S) 3.0(Hole) 7-9 3.0(L/S) 3 5 More Function (Option) Basic × (Option) × (Option) Precision Metrology Lab. Advanced Meas. function Layer 1 Layer 2 Layer 3 Structure SEM Image Example of Middle Layer measurement AOI Lecture Precision Metrology Lab. Imaging capability t=2.0 µm BPSG 2µm =138 nm =101 nm Ability for observation (Aspect ratio 20:1) AOI Lecture Precision Metrology Lab. Process Variation Monitoring Focus -0.5 0.203 0.1 0.201 [μm] -0.3 0.199 -0.1 0.216 0.3 0.198 0.5 0.189 Bottom CD is almost the same but shape is totally different AOI Lecture Precision Metrology Lab. Requirement for CD Measurement Tool Stactic Repeatability Dynamic Repeatability Magnification Linearity Resolution Matching Low Charging effect High Throughput Remote data analysis Good Pattern Recognition AOI Lecture line hole 2nm 3nm 1nm 3nm 3nm 5nm Precision Metrology Lab. Micro Defect Inspection Tool Introduction US$ 6,500,000 AOI Lecture US$ 2,500,000 Precision Metrology Lab. Poly 2 AEI BRIDGE ISSUE WSIE-01A AOI Lecture Precision Metrology Lab. Tools for in-line monitoring & analysis Type C : UV inspector ability for metal ADI/AEI pattern defects Metal AEI dot pattern mission Metal ADI PR. Defects inspected Metal AEI PR. Defects inspected AOI Lecture Precision Metrology Lab. Metal AEI GALVANIC Cell Issue Seriously GALVANIC Cell defect, it happened at specific pattern as below image Galvanic cell: AOI Lecture Precision Metrology Lab. Metal 3 AEI TestKey Scan Result I.Defect Map & counts: II.Defect Image:all are GALVANIC CELL defect seriously. AOI Lecture Precision Metrology Lab. KLA-Tencor USA Micro AOI 90 – 65 nm Open contact Line narrow Resist stringers Features: Broadband illumination (DUV/UV/VIS 200-900nm, Xe lamp, Rotary filter plate High NA (0.9), Enhanced image resolution, High performance edge contrast mode Bright light Price: 6.5 M US$ AOI Lecture Precision Metrology Lab. Macro Defect Inspection Tool Introduction AOI Lecture Precision Metrology Lab. Typical Rework Data Based on Fab Data Input CD OL No t S e e n Process Defect D e te c te d Other Macro Detected Process defects contribute about 1/4 of rework - Varies by fab AOI Lecture Operators only see 20-25% of defects Micro Macro makes up ~1/3 of defect rework Precision Metrology Lab. Lithography Problems Found at Visual ADI – Around 9% of total Rework Hot spots EBR Edge-Bead Removal Contamination Particles Foreign materials Scratches Handling errors Tool misadjustment Coating Missing/extra Splashback Striations Comets No resist AOI Lecture Missing Wrong width Miscentering Develop Scumming Developer spots No develop Exposure Missing Focus error Gross misalign Aperture blade error No exposure Precision Metrology Lab. Inspection Methods Brightlight station Integrated in station Macro Insp. tool Time per wafer (sec.) 5-20 none -5 45 70-150 µm? 70-150 µm? 50 µm Inspection consistency poor very poor good Classification consistency poor poor good wafer count wafer count Defect, die count Yield information no no yes/Quest Process improvement no no yes/Quest Sensitivity Rework information AOI Lecture Precision Metrology Lab. Defect Detection Concurrent Detection in Darkfield & Brightfield Field-Field Comparison • Detects random defects • • • • • • • Hot spots Particles Scratches Bad spin Missed field Developer spots Etc. Simultaneous ADC • Classifies comparison result • Rule-based classification • Classifies scratches, particles • Roadmap includes more classes • 50 µm sensitivity Full-wafer errors • No resist, no develop, no exposure • To be added in next software • Comparison to reference image AOI Lecture Precision Metrology Lab. Stepper Defocus Resist/Si, Includes Scratch Dark Field Image Bright Field Image Tweezers Marks Hot Spots Scratches AOI Lecture Precision Metrology Lab. Bad Resist Spin Implant Dark Field Image AOI Lecture Bright Field Image Bad Spin Scratches Precision Metrology Lab. Hot Spot Metal 3 Hot spot Dark Field Image AOI Lecture Bright Field Image Scratches Precision Metrology Lab. Bad Resist Spin 0.25 µm Via Dark Field Image AOI Lecture Bright Field Image Precision Metrology Lab. Thin Film thickness Measurement Spectral analysis of reflectance from the top and bottom of the thin film provides thickness and refractive index coefficient in seconds. AOI Lecture Precision Metrology Lab. IC AOI Lecture AOI Precision Metrology Lab. IC Inspection System: Software Flow Chart For Packaging process Capture IC Image from CCD Defect Inspect of Number of Pins and Pin Distances Source from: AOI Lecture Segment Image and Perform a Binary Operation Process Image and Get Features Defects Inspect of IC Printed Mark Precision Metrology Lab. IC [ ] [ ] [ ] [ ] [ [ ] ] [ ] [ ] [ ] [ ] [ [ ] ] [ ] [ ] [ [ ] ] [ [ ] [ [ ] [ ] [ ] [ ] [ [ [ [ AOI Lecture ] ] ] [ ] [ [ ] ] ] ] ] Precision Metrology Lab. Wire Bond Defect Inspection AOI Lecture Precision Metrology Lab. AOI Lecture Precision Metrology Lab. AOI Lecture Precision Metrology Lab. Images of bonding wire under different lighting angles 60 o 30 o AOI Lecture 45 o 15 o Precision Metrology Lab. LED AOI Lecture Precision Metrology Lab. a AOI Lecture b c Precision Metrology Lab. Bonding Ball Inspection -- variant shapes of bonding ball contour AOI Lecture Precision Metrology Lab. Experimental results of bonding ball searching AOI Lecture Precision Metrology Lab. b AOI Lecture Precision Metrology Lab. IC Pin Inspection System AOI Lecture Precision Metrology Lab. IC Ink Mark Classification Bad contrast Partial bad contrast Double prints Mis-orientation Up-side down Distortion Missing ink Partial missing ink Mis-printed Scraped Blob Broken Smeared Standard AOI Lecture Precision Metrology Lab. IC Ink Mark Inspection System • Defect types - Smeared - Scraped & Broken - Missing ink - Mis-printed - Partial Missing ink - Mis-orientation • Inspection time - 0.54 second AOI Lecture Precision Metrology Lab. Defects-Gold Nodule Nodule Nodule Nodule Cu Exposed Cu Exposed Cu Exposed Cu Exposed Cu Exposed Cu Exposed Cu Exposed 55 2014/5/10 Precision Metrology Lab. Defects-SR Gold Exposed Gold Exposed Scratch FM FM FM Crack 56 2014/5/10 Precision Metrology Lab. Homework for IC (or Wafer) Inspection Please visit the website of Solid State Review to find any new technology, and rewrite into a report: http://www.solid-state.com AOI Lecture Precision Metrology Lab.
© Copyright 2024 ExpyDoc
