Failure Analysis (FA) is a body of tests and procedures to identify failure mechanisms in semiconductor and MEMS circuits. A wide range of tests and procedures has been developed to identify the location and nature of the fault.

Micromanipulator has been providing equipment to support failure analysis in semiconductors since 1956 and has a wide range of products designed to assist the FA professional. The models listed below are a small selection of what is available from Micromanipulator. Contact your local Micromanipulator Sales Representative for assistance in selecting appropriate equipment for specific FA tests.

Analysis can identify

• Faulty circuit design
• Production errors
• In-field device damage

Typical Probe system requirements

Test	Type of Probing	Samples	Sample Type	Smallest Structure Size	Temperature
Faulty Circuit Design	Interactive	Many	Wafer Pieces	<1µm	-65° to +400°C
Production Errors	Automated	Many	Wafer Pieces Packaged	<1µm	Ambient to +400°C
In-field Device Damage	Interactive	Few	Packaged	<1µm	0° to +400°C

Systems which support

• Faulty circuit design: P200A/P300A semiautomatic probe stations, H1000 thermal chuck system
• Production errors: P200A/P300A semiautomatic probe stations, H1000 thermal chuck system
• In-field device damage: 4000/8000/P300J manual probe stations, H1000 thermal chuck system

Tests include

• Locating defects
• Image analysis
• Micro-sectioning to uncover defects
• Electrical test measurements
• Micro-motion MEMS analysis

Micromanipulator Supported FA Tests

FA Tests	Typical Requirements	Models Supporting Test
Visual examination: >0.5µm	*High magnification microscope *Image enhanced video *Vibration free platform	*Seiwa PS, FS70, A-Zoom microscopes *Advanced video systems *LTE + Vib. table system
Liquid crystal (during bias)	*Thermal chuck system *Microscope polarizing filters	*H1000 Thermal chuck system with pcTC control *Microscope polarizer kits
Low light emission microscope (during bias)	*Emission camera system *Low loss microscope *Light shield	FA-2000 emission microscope system
Micro-sectioning	*Laser cutters (Green, near UV and near IR) *Vibration free probe station	*New Wave laser cutters *4000/8000/P200-300 series stations *Vibration isolation tables
Micro-motion analyzers	*In-plane and Out-of-plane vibration analyzer *Vibration free probe station	*4000/8000/P200-300 series stations *Vibration isolation tables
Resistance/Continuity: 2-wire and 4-wire	Kelvin Probes	44-D, 44-DA, 44-J, 44-H, 44-DS, 79-D, 81-D, 81-SD probes/probe holders
Capacitance-Voltage (CV) : 4TP	Kelvin Probes	44-DA, 79-D probes/probe holders
Current-Voltage (IV)	*Low current (femtoamp/attoamp) test system *Light/EMI shielding *Vibration free system *Uniform contact resistance	*8000/P200-300 series probe stations *79-T low current probe holder *Integrated LTE/Vibration isolation tables *HCT and 7S/7F/7F-10C high compliant probe tips
Optical stimulation: OBIRCH/LIVA/TIVA	*Move spot of light/IR across circuit *Low current probes *Thermal stability	*P200A/P300A semiautomatic stations *79T low current probe holder *New Wave lasers *VWBH-SET Mini-clamp system *H1000 thermal chuck system

Liquid crystals are used in testing semiconductors to locate defects which generate heat and in analyzing power distribution in semiconductor devices. Liquid crystal will show circuit hot spots, where the temperature of the circuit is higher than the surrounding area. Liquid crystal can be used with great sensitivity to locate a wide range of defects.

Typical faults detected by Liquid Crystal analysis

• Gate Oxide Breakdown
• Floating gates
• Missing polysilicon
• Silicon Oxide pinholes
• Intermittent shorts
• Leakage under Aluminum

Often the defect area can be more precisely located by reducing the test sample’s temperature by a few tenths of a degree Celsius. Therefore, many liquid crystal test systems use thermal chucks which precisely control the sample temperature.

Liquid crystal is a complementary technology to photoemission microscopy. Photoemission microscopy can precisely identify sites which emit low level light in the 280nm to 1200nm range. Liquid crystal detection may be performed with the microscope used with the FA-2000™ emission microscope system. The microscope may be equipped with a polarizer/analyzer option for use with liquid crystal work. The color/darkness changes typical of liquid crystal detection can be viewed with the eyepieces or with the FA-2000™ camera, which provides real time imaging. At the same time, defects that emit light can be imaged by the FA-2000™. The combined power of detection of heat (liquid crystal) and detection of light (photoemission) may greatly speed the identification of circuit faults.

An Application Note is available on Liquid Crystal Testing along with a second Application Note which provides information on liquid crystal materials and other test kit materials.