Optimal production test times through adaptive test programming

Abstract The intent of this work is to demonstrate the importance of charged device model (CDM) ESD testing and characterization by presenting a case study of a situation in which CDM testing proved invaluable in establishing the reliability of a GaAs radio frequency integrated circuit (RFIC). The problem originated when a sample of passing devices was retested to the final production test. Nine of the 200 sampled devices failed the retest, thus placing the reliability of all of the devices in question. The subsequent failure analysis indicated that the devices failed due to a short on one of two capacitors, bringing into question the reliability of the dielectric. Previous ESD characterization of the part had shown that a certain resistor was likely to fail at thresholds well below the level at which any capacitors were damaged. This paper will discuss the failure analysis techniques which were used and the testing performed to verify the failures were actually due to ESD, and not caused by weak capacitors.

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ATE Failure Isolation Methodologies for Failure Analysis, Design Debug and Yield Enhancement

ISTFA 1998: Conference Proceedings from the 24th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1998p0235 ◽

1998 ◽

Author(s):

D.S. Patrick ◽

L.C. Wagner ◽

P.T. Nguyen

Keyword(s):

Integrated Circuits ◽

Failure Analysis ◽

Yield Enhancement ◽

Production Test ◽

Final Test ◽

Critical Design ◽

The Past ◽

Product Engineering ◽

Time Savings ◽

Analysis Design

Abstract Failure isolation and debug of CMOS integrated circuits over the past several years has become increasingly difficult to perform on standard failure analysis functional testers. Due to the increase in pin counts, clock speeds, increased complexity and the large number of power supply pins on current ICS, smaller and less equipped testers are often unable to test these newer devices. To reduce the time of analysis and improve the failure isolation capabilities for failing ICS, failure isolation is now performed using the same production testers used in product development, multiprobe and final test. With these production testers, the test hardware, program and pattern sets are already available and ready for use. By using a special interface that docks the production test head to failure isolation equipment such as the emission microscope, liquid crystal station and E-Beam prober, the analyst can quickly and easily isolate the faillure on an IC. This also enables engineers in design, product engineering and the waferfab yield enhancement groups to utilize this equipment to quickly solve critical design and yield issues. Significant cycle time savings have been achieved with the migration to this method of electrical stimulation for failure isolation.

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Temperature-Dependent Logic Failure in a GaAs Power Amplifier-Duplexer Module Caused by a Subtle Parasitic Schottky Diode

ISTFA 2014: Conference Proceedings from the 40th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2014p0450 ◽

2014 ◽

Author(s):

Rose Emergo ◽

Steve Brockett ◽

Pat Hamilton

Keyword(s):

Power Amplifier ◽

Schottky Diode ◽

Production Test ◽

Temperature Dependent ◽

Cold Temperatures ◽

Collector Junction ◽

Power Mode ◽

The Difference ◽

Base Contact ◽

Single Power

Abstract A single power amplifier-duplexer device was submitted by a customer for analysis. The device was initially considered passing when tested against the production test. However, further electrical testing suggested that the device was stuck in a single power mode for a particular frequency band at cold temperatures only. This paper outlines the systematic isolation of a parasitic Schottky diode formed by a base contactcollector punch through process defect that pulled down the input of a NOR gate leading to the incorrect logic state. Note that this parasitic Schottky diode is parallel to the basecollector junction. It was observed that the logic failure only manifested at colder temperatures because the base contact only slightly diffused into the collector layer. Since the difference in the turn-on voltages between the base-collector junction and the parasitic Schottky diode increases with decreasing temperature, the effect of the parasitic diode is only noticeable at lower temperatures.

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