Failure Analysis From Back Side of Die

Author(s):  
N.M. Wu ◽  
K. Weaver ◽  
J.H. Lin

Abstract With increasing complexity of circuit layout on the die and special packages in which the die are flipped over, failure analysis on the die front side, sometimes, can not solve the problems or is not possible by opening the front side of the package to expose the die front side. This paper discusses fault isolation techniques and procedures used on the back side of the die. The two major back side techniques, back side emission microscopy and back side OBIC (Optical Beam Induced Current), are introduced and applied to solve real problems in failure analysis. A back side decapsulation technique and procedure are also introduced. Last, several examples are given. The results indicated that the success in finding root cause of failure is greatly increased when these techniques are used in addition to the traditional front side analysis approaches.

Author(s):  
Yoav Weizman ◽  
Ezra Baruch ◽  
Michael Zimin

Abstract Emission microscopy is usually implemented for static operating conditions of the DUT. Under dynamic operation it is nearly impossible to identify a failure out of the noisy background. In this paper we describe a simple technique that could be used in cases where the temporal location of the failure was identified however the physical location is not known or partially known. The technique was originally introduced to investigate IDDq failures (1) in order to investigate timing related issues with automated tester equipment. Ishii et al (2) improved the technique and coupled an emission microscope to the tester for functional failure analysis of DRAMs and logic LSIs. Using consecutive step-by-step tester halting coupled to a sensitive emission microscope, one is able detect the failure while it occurs. We will describe a failure analysis case in which marginal design and process variations combined to create contention at certain logic states. Since the failure occurred arbitrarily, the use of the traditional LVP, that requires a stable failure, misled the analysts. Furthermore, even if we used advanced tools as PICA, which was actually designed to locate such failures, we believe that there would have been little chance of observing the failure since the failure appeared only below 1.3V where the PICA tool has diminished photon detection sensitivity. For this case the step-by-step halting technique helped to isolate the failure location after a short round of measurements. With the use of logic simulations, the root cause of the failure was clear once the failing gate was known.


2013 ◽  
Vol 21 (3) ◽  
pp. 30-35
Author(s):  
Douglas Martin ◽  
Samuel Beilin ◽  
Brett Hamilton ◽  
Darin York ◽  
Philip Baker ◽  
...  

Failure analysis is important in determining root cause for appropriate corrective action. In order to perform failure analysis of microelectronic application-specific integrated circuits (ASICs) delidding the device is often required. However, determining root cause from the front side is not always possible due to shadowing effects caused by the ASIC metal interconnects. Therefore, back-side polishing is used to reveal an unobstructed view of the ASIC silicon transistors. This paper details how back-side polishing in conjunction with laser-scanned imaging (LSI), laser voltage imaging (LVI), laser voltage probing (LVP), photon emission microscopy (PEM), and laser-assisted device alterations (LADA) were used to uncover the root cause of failure of two ASICs.


Author(s):  
Wong Yaw Yuan ◽  
T.L. Edmund Poh ◽  
David Lam

Abstract The migration to smaller geometries has translated to an increase in the number of transistors possible in each integrated circuit. Failure analysis of such complex circuits presents a major challenge to the semiconductor industry and is a driving force behind the considerable interest in nondestructive, cost-efficient, “shortcut” fault isolation techniques. In this paper, we present the application of thermal-induced voltage alteration (TIVA) for failure analysis of 0.11µm technology memory devices and demonstrate the key aspects of this technique. The back side TIVA results are compared with analysis performed using back side emission microscopy (EMMI), and the limitations of EMMI are highlighted. The advantages and limitations of the TIVA technique are also discussed.


Author(s):  
Tommaso Melis ◽  
Emmanuel Simeu ◽  
Etienne Auvray

Abstract Getting accurate fault isolation during failure analysis is mandatory for success of Physical Failure Analysis (PFA) in critical applications. Unfortunately, achieving such accuracy is becoming more and more difficult with today’s diagnosis tools and actual process node such as BCD9 and FinFET 7 nm, compromising the success of subsequent PFA done on defective SoCs. Electrical simulation is used to reproduce emission microscopy, in our previous work and, in this paper, we demonstrate the possibility of using fault simulation tools with the results of electrical test and fault isolation techniques to provide diagnosis with accurate candidates for physical analysis. The experimental results of the presented flow, from several cases of application, show the validity of this approach.


2018 ◽  
Author(s):  
Yuting Wei ◽  
Chuan Zhang ◽  
Liangshan Chen ◽  
Oh Chong Khiam

Abstract E-beam induced current technique is a fault isolation technique based on SEM-based nanoprobers. Electron beam induced current (EBIC) can help failure analysts quickly identify the defective device with abnormal junction behavior from a relatively large area of interest. Using EBIC, defects can be pin-pointed down to individual Fin, which significantly enhanced the success rate. In this paper, two cases are used as examples to illustrate how this failure analysis (FA) methodology provides a powerful and efficient solution in localizing defective fins. In the first case, a local full bit-line fail was submitted for failure analysis. In the second case, a MOS capacitor parametric test structure designed to monitor gate oxide break down voltage that showed early break down behavior during in-line test. Failure analysis was requested to investigate the root-cause.


1996 ◽  
Author(s):  
Nevil M. Wu ◽  
Kenneth Tang ◽  
James H. Lin

Author(s):  
Hasan Faraby ◽  
Tristan Deborde ◽  
Martin von Haartman

Abstract This paper analyzes the through-put time and output of fault isolation and failure analysis (FI/FA) flows on state-of-the-art microprocessors. An average reduction in through-put time of 40% was demonstrated with a shortened FI/FA flow while still maintaining a high success rate. The direct FA/nano-probing flow which was utilized by up to around 90% of the fail cases omitted the optical fault isolation step and instead expanded the use of plasma FIB, nano-probing and electrical isolation techniques (such as diagnosis tools). The end result is shorter through-put time and higher FI/FA volume which is important in order to achieve a faster production ramp. In the paper two cases studies are presented to demonstrate the new efficient FI/FA techniques.


Author(s):  
Eric Barbian ◽  
Rommel Estores

Abstract This paper will present a practical implementation of ATPG testing and diagnosis in Failure Analysis resulting in a fast and efficient iterative ATPG diagnosis and fault isolation. On this implementation, a compact test HW instead of an ATE is used for cost-effective ATPG testing and characterization capability. The advantages of this implementation are combined with ATPG tools to make it possible to achieve a faster and more efficient implementation of iterative ATPG diagnosis, Dynamic Analysis by Laser Stimulation (DALS) analysis or similar techniques. The requirements needed in order to implement ATPG testing and diagnosis in FA lab will be discussed. Success in determining root cause, especially on the complex analysis cases is determined by the complimentary combination of various fault isolation techniques. Knowledge of the fundamentals of these techniques combined with creative thinking process of the analyst leads to the approaches and solutions that maximize the combined advantages of these techniques.


Author(s):  
Hua Younan ◽  
Chu Susan ◽  
Gui Dong ◽  
Mo Zhiqiang ◽  
Xing Zhenxiang ◽  
...  

Abstract As device feature size continues to shrink, the reducing gate oxide thickness puts more stringent requirements on gate dielectric quality in terms of defect density and contamination concentration. As a result, analyzing gate oxide integrity and dielectric breakdown failures during wafer fabrication becomes more difficult. Using a traditional FA flow and methods some defects were observed after electrical fault isolation using emission microscopic tools such as EMMI and TIVA. Even with some success with conventional FA the root cause was unclear. In this paper, we will propose an analysis flow for GOI failures to improve FA’s success rate. In this new proposed flow both a chemical method, Wright Etch, and SIMS analysis techniques are employed to identify root cause of the GOI failures after EFA fault isolation. In general, the shape of the defect might provide information as to the root cause of the GOI failure, whether related to PID or contamination. However, Wright Etch results are inadequate to answer the questions of whether the failure is caused by contamination or not. If there is a contaminate another technique is required to determine what the contaminant is and where it comes from. If the failure is confirmed to be due to contamination, SIMS is used to further determine the contamination source at the ppm-ppb level. In this paper, a real case of GOI failure will be discussed and presented. Using the new failure analysis flow, the root cause was identified to be iron contamination introduced from a worn out part made of stainless steel.


Author(s):  
Y. N. Hua ◽  
Z. R. Guo ◽  
L. H. An ◽  
Shailesh Redkar

Abstract In this paper, some low yield cases in Flat ROM device (0.45 and 0.6 µm) were investigated. To find killer defects and particle contamination, KLA, bitmap and emission microscopy techniques were used in fault isolation. Reactive ion etching (RIE) and chemical delayering, 155 Wright Etch, BN+ Etch and scanning electron microscope (SEM) were used for identification and inspection of defects. In addition, energy-dispersive X-ray microanalysis (EDX) was used to determine the composition of the particle or contamination. During failure analysis, seven kinds of killer defects and three killer particles were found in Flat ROM devices. The possible root causes, mechanisms and elimination solutions of these killer defects/particles were also discussed.


Sign in / Sign up

Export Citation Format

Share Document