Technologies such as microscopy and X-ray are the venerable grandparents of the inspection industry. Others, like scanning probe microscopy and reverse geometry X-ray, are the bright young upstarts. Each has its place–its niche market where it performs best.
But all inspection products have one thing in common: Their manufacturers are not resting on their laurels. They are constantly innovating and refining technologies to keep up with the smaller, denser geometries of surface-mount devices and newer package types that seem to develop almost daily.
For example, the scanning probe microscope used for atomic scale inspection and metrology of semiconductors has demonstrated many improvements since its invention in 1981. Some breakthroughs combine atomic force and tunneling sensor modes, allowing both contact and noncontact inspection of semiconductors.
Ergonomics plays an important role in the design of newer microscopes, enabling you to work longer without fatigue. The ErgoZoom feature on the Leica microscopes provides a smooth, easy motion to travel through a wide zoom range without tiring the operator.
Real-time X-ray techniques including cross-sectional imaging help detect solder-joint defects on PCBs and measure solder joints and plated through-hole solder volume. Some companies, such as Four Pi, also offer the capability to inspect both sides of a double-sided board in one pass.
Where is inspection going from here? Most likely to even more automation as feature size and defect tolerance decrease. Automation enables you to view and validate submicron structures, which is critical when inspecting shrinking solder joints.
Look, too, for more precision in the nonautomated applications. These tasks still require equipment that is steady, accurate and designed for extended use without unduly tiring the operator. And modular design cannot be forgotten since it is the major source for increasing product configurations and tailor-made solutions for your specific inspection needs.
Inspection Products
Station Checks 100
Inspection Points Per Program
The Model LFI 3060 is a programmable X-Y station for inspecting MCMs, array-type lead frames and large die areas. The machine allows 100 inspection points per program and programmable speed scan lines in a 2″ x 2″ area. A track-ball system is included for manual override of the program. The system typically is used with a 30X microscope and CCTV for device inspection. Lot identification, device type information and other data can be downloaded to a data collection center for yield and performance analyses. $28,800 plus optics. ALLTEQ Industries Inc., (510) 770-8181.
Video System Has Measuring
And Marking Capabilities
The VIA-170R Video Image Marker-Measurement System inspects video images for microscopic or macroscopic applications. It connects between a camera or VCR and a monitor and generates a graphic overlay on the live or stored image. Graphics and measuring lines may be positioned on the overlay to mark the image. Ten measurement capabilities are provided. An align feature for positioning markers in unison over important aspects of the image assists go, no-go inspection. $3,795. Boeckeler Instruments, Inc., (800) 552-2262.
Reverse Geometry X-Ray Detects
Solder Volume Variations
The RGXTM Reverse Geometry X-Ray System provides a 10″ dia X-ray source with a 1.5″ to 10″ dia field of view (FOV). Spatial resolution is 12 line pairs/mm for 3″ FOV, 10 line pairs/mm for 1.5″ FOV and 4.5 line pairs/mm for 10″ FOV. The system supplies an area magnification from 1X to 100X and a detector with >99% efficiency. The source-to-detector distance varies from 3″ to 30″. A stereoscopic 3-D monitor, a VCR and RS-343 ports are available. $200,000. Digiray Corp., (510) 838-1510.
Focused Ion Beam Supports
0.5-Micron Monitoring
The FIB 800 Workstation supports 8″ wafer fabrication for process monitoring and production yield management of sub 0.5-micron devices. The automated station provides micromachining, metal deposition and a scanning ion microscopy capability for cutting, viewing, device modification and failure analysis. A wafer-introduction system and sample stage minimize particle contamination during wafer handling. A five-axis 8″ stage places beams precisely on planarized stages. An ion-column and imaging system provides required resolution for defect-related applications. FEI Co., (503) 640-7500.
Real-Time X-Ray
Magnifies Objects 1,080X
The Model FXS-100.25 Realtime Microfocus X-Ray System now has the capability to magnify a test sample 1,080X. The filament and target of the X-ray source are replaceable. A new click-in cathode assembly enables the user to easily change the X-ray filament. The circular focal spot size is <5 micron; the maximum output is 100 kV. FeinFocus USA, Inc., (404) 717-0179. 32035Cross-Sectional Imaging
Detects Defects on BGAs
The 5DX Automated Process Test System uses cross-sectional X-ray imaging to inspect and measure solder joints on PCB assemblies with surface-mount or ball grid array (BGA) components. Throughput is 50 joints/s to 150 joints/s. Solder thicknesses from 0.5 mil to 25 mils are measured with a repeatability standard deviation of <4%. Data including heel fillet height and average solder thickness are collected to provide real-time control charts. Data filters help select the desired measurement data. Starting at $300,000. Four Pi Systems, (619) 485-8551.
ISO Calibration
Workbook Offered
The ISO Calibration System Workbook is a guide for quality system auditors. The 86-page publication helps users perform internal audits of calibration and testing systems and external audits of suppliers’ calibration and testing systems. A checklist helps verify conformance to the latest ISO calibration standards. A list of calibration standards and calibration forms also are furnished. $14.95. Integrated Management Resources, Inc., (708) 369-8444.
CAD Navigation Software
Handles 16 Million Transistors
The Merlin’s Framework high-performance CAD navigation software handles up to 16 million transistor designs. This upgrade to the Merlin I features faster display time for IC designs, improved memory management with 400% reduction in swap space, and wafer or defect navigation capability. The response time to signal highlighting between netlist and layout views has been improved. A schematic option is available for displaying an EDIF schematic file. $85,000. Knights Technology, Inc., (408) 988-0600.
Microscope Has Constant Focus
And 1:8 Magnification
The WILD MZ8 Stereomicroscope provides a 1:8 zoom and retains focus when the magnification is changed. The modular design allows modifications and the addition of accessories. It offers a choice of binocular tubes, eyepieces and stands, and interchangeable objectives. The microscope provides coarse and fine focus drives. Interchangeable planachromat and achromat objectives are available. Starting at $3,200. Leica Inc., (708) 405-0123.
X-Ray System Allows
Programming of X-Y Stages
The Model 2001HM-A X-Ray Inspection System is an automatic real-time microfocus unit with a 12″ x 12″ table. It allows the user to program the movement of the X and Y stages and adjust the Z axis for appropriate magnification. Programmed inspection sequences can be stored. The system also operates in the manual mode. $135,000 to $150,000. Lixi, Inc., (708) 620-4646.
Monoscope Offers 3-D Effect
With 8″ Working Distance
The Super 3-D Monoscope provides a resolution of 102 line pairs/mm at 5X magnification and a depth of field of 15 mm at an 8″ working distance. The working distance allows room for soldering and assembly. It does not require two-eye alignment. $4,750. Metron Optics, Inc., (619) 755-4477.
System Performs In-Line
Monitoring of Solder Joints
The CXI-3600CS In-Line Process Monitor combines conveyor board handling and variable field of view (FOV) with microfocus real-time X-ray imaging of SMT assemblies. Inspection rates exceed 100 joints/s. The variable FOV allows users to zoom in on fine-pitch components while inspecting standard pitch components. Typical inspection time per view is 400 ms. $325,000 to 375,000. Nicolet Imaging Systems, Inc., (608) 276-6383.
System Allows Linking of
Data to SPC Software
The OPTEK DMS Desktop Measuring System permits real-time linking of dimensional data to optional statistical process control software. It provides a precise field-of-view measuring capability for laboratory or production-line requirements. A frame grabber card and video software automatically perform pixel analysis. Lenses are offered in fixed and zoom formats with magnifications from 25X to 1,200X. Operations Technology, Inc., $19,500. (908) 362-6200.
System Performs Contact
And Noncontact Measurements
The AutoProbeR VP is an atomic resolution scanning probe microscope that performs scanning tunneling and atomic force microscopy (AFM) in an ultra-high vacuum. The scanning probe touches the sample surface when used in the contact AFM mode and can also perform noncontact measurements. It is used to conduct atomic resolution surface studies on semiconductor samples, data-storage products and composites without applying a conductive coating. The VP can be used alone or incorporated into other equipment. $240,000. Park Scientific Instruments, (408) 747-1600.
Confocal Microscope Provides
Sub Half-Micron Resolution
The K2 – FA Confocal Scanning Optical Microscope resolves sub half-micron detail, provides real-time imaging and has two confocal modes. Applications include nondestructive inspection of products in the semiconductor, materials-science and chemical industries. The microscope offers coarse and fine adjustment and binocular viewing. Optional 3-D software is available. $30,000. Technical Instrument Co., (415) 431-8231.
Scanning Microscope Measures
Thermal Features of Structures
The Scanning Thermal Microscopy (SThM) feature of the TMX 2000 Atomic Force Microscope measures the thermal characteristics and features of structures. A control unit sends thermal image signals to the electronic control unit via an analog-to-digital converter. The SThM probe is constructed of wire with a platinum core. The force between the probe and the sample provides thermal and topographic information. It is used in material-sciences and electronic-component failure analysis. $16,000. TopoMetrix, (408) 982-9700.
Measurement System Provides
Resolution of 0.1 µm
The VoyagerTM 1000 Model 612 is a vision-based, noncontact dimensional measurement system. The stage positioning resolution is 0.1 micron, the X-Y area measurement accuracy is 9 microns, and the Z linear accuracy is ±7.5 microns. Coaxial lighting for image illumination can be controlled manually and by computer. The system provides WindowsTM-based software for automatic, semiautomatic and manual control. Software functions include 2-D and 3-D part and fixture alignment, and point, line and plane definitions. $50,000. View Engineering, Inc., (805) 522-8439.
Stereo Viewer Provides
Magnification from 2X to 10X
The Mantis Stereo Viewer provides linear magnification from 2X to 10X at a working distance of 7″ to 1.7″, respectively. The unit reduces operator eye strain and muscle fatigue by projecting images onto a high-resolution screen. Lighting is provided by two 12-V, 20-W dichroic reflector lamps. Applications include assembly, rework, PCB repair and quality-control inspection. $1,600. Vision Engineering, Inc., (203) 355-3776.
System Inspects PCB
Solder-Pad Integrity
The MCRS-100 PCB X-Ray Inspection System checks the solder-pad integrity of conventional and ball grid array surface-mount components. The off-line, manually operated system inspects populated boards 18″ x 24″. High-resolution positioning and image processing help the operator collect statistical information and make appropriate board-quality decisions. $85,000. Philips Industrial X-Ray, (404) 368-4420.
Wafer Inspection System
Offers Throughput of 25 wph
The IQ 1850 is a patterned wafer defect inspection system that provides a throughput of 25 wafers per hour and digital image processing capability. It utilizes optical pattern filtering and a die-to-statistical-imaging technology, enabling resolution to 0.2 micron. The system is used to find repetitive and nonrepetitive defective IC patterns and to reduce false defects by comparing die patterns to a reference image. $1,350,000. Optical Specialties, Inc. (510) 490-6400.
Thermal Wave Option
Provides Depth Information
The Lock-In Thermal Wave option for the ThermovisionR 900 IR System provides depth information and locates voids and cracks several millimeters below the surface. The product generates a thermal wave through the object under inspection with the low- frequency modulation of a laser, halogen lamp or hot-air gun. Pixels on the sample are monitored and thermographic images are recorded during each modulation cycle. AGEMA Infrared Systems Inc., (201) 867-5390.
Copyright 1995 Nelson Publishing Inc.
February 1995