Power-on contention: a reliability issue for logic devices

Utilizing Nanoprobing and Circuit Diagnostics to Identify Key Failure Mechanism of Otherwise Nonvisible Defects in 20 nm Logic Devices

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

10.31399/asm.cp.istfa2014p0196 ◽

2014 ◽

Author(s):

M.K. Dawood ◽

C. Chen ◽

P.K. Tan ◽

S. James ◽

P.S. Limin ◽

...

Keyword(s):

Failure Analysis ◽

Contact Layer ◽

Fault Isolation ◽

Tem Analysis ◽

Logic Devices ◽

Technology Advancement ◽

Transmission Electron ◽

Voltage Contrast ◽

Almost All ◽

20 Nm

Abstract In this work, we present two case studies on the utilization of advanced nanoprobing on 20nm logic devices at contact layer to identify the root cause of scan logic failures. In both cases, conventional failure analysis followed by inspection of passive voltage contrast (PVC) failed to identify any abnormality in the devices. Technology advancement makes identifying failure mechanisms increasingly more challenging using conventional methods of physical failure analysis (PFA). Almost all PFA cases for 20nm technology node devices and beyond require Transmission Electron Microscopy (TEM) analysis. Before TEM analysis can be performed, fault isolation is required to correctly determine the precise failing location. Isolated transistor probing was performed on the suspected logic NMOS and PMOS transistors to identify the failing transistors for TEM analysis. In this paper, nanoprobing was used to isolate the failing transistor of a logic cell. Nanoprobing revealed anomalies between the drain and bulk junction which was found to be due to contact gouging of different severities.

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Decapsulation Techniques for Cu Wire Bonding Package

ISTFA 2009: Conference Proceedings from the 35th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2009p0217 ◽

2009 ◽

Author(s):

Dongmei Meng ◽

Joe Rupley ◽

Chris McMahon

Keyword(s):

Laser Ablation ◽

Thin Layer ◽

Chemical Etching ◽

Wire Bonding ◽

Methods And Techniques ◽

Wet Chemical ◽

Wet Chemical Etching ◽

Reliability Issue ◽

Etch Time ◽

Device Technology

Abstract This paper presents decapsulation solutions for devices bonded with Cu wire. By removing mold compound to a thin layer using a laser ablation tool, Cu wire bonded packages are decapsulated using wet chemical etching by controlling the etch time and temperature. Further, the paper investigates the possibilities of decapsulating Cu wire bonded devices using full wet chemical etches without the facilitation of laser ablation removing much of mold compound. Additional discussion on reliability concerns when evaluating Cu wirebond devices is addressed here. The lack of understanding of the reliability of Cu wire bonded packages creates a challenge to the FA engineer as they must develop techniques to help understanding the reliability issue associated with Cu wire bonding devices. More research and analysis are ongoing to develop appropriate analysis methods and techniques to support the Cu wire bonding device technology in the lab.

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