Cavity Up and Stack Die Backside Failure Analysis for Thin Die and High Pin Count Devices

Author(s):  
Dat Nguyen ◽  
Thao To ◽  
Ray Harrison ◽  
Cuong Phan ◽  
John Drummond

Abstract Owing to the configuration of cavity up and stacked die packaging and the requirements of backside analysis, both packaging types require similar sample preparation steps. This article describes the failure analysis (FA) process to be applied with cavity up and stack die packages. The FA process flow includes testing to determine the nature of the failure, failure correlation to chip and/or internal circuitry, die preparation for repackaging, die repackaging in a cavity down configuration, automated test equipment (ATE) testing to verify the integrity of the pre-packaging failure mode, backside thinning, global fault isolation, backside reconstruction, and defect identification by front side deprocessing. ATE FA can often be performed using special analysis modes and the modification of the test software to put tester in a halt or a loop during fault isolation. When this is completed, global FA techniques can be used. The article also presents a case study on the successful repackaging efforts of cavity up packages.

Author(s):  
Gil Garteiz ◽  
Javeck Verdugo ◽  
David Aveline ◽  
Eric Williams ◽  
Arvid Croonquist ◽  
...  

Abstract In this paper, a failure analysis case study on a custom-built vacuum enclosure is presented. The enclosure’s unique construction and project requirement to preserve the maximum number of units for potential future use in space necessitated a fluorocarbon liquid bath for fault isolation and meticulous sample preparation to preserve the failure mechanism during failure analysis.


Author(s):  
Andrew J. Komrowski ◽  
N. S. Somcio ◽  
Daniel J. D. Sullivan ◽  
Charles R. Silvis ◽  
Luis Curiel ◽  
...  

Abstract The use of flip chip technology inside component packaging, so called flip chip in package (FCIP), is an increasingly common package type in the semiconductor industry because of high pin-counts, performance and reliability. Sample preparation methods and flows which enable physical failure analysis (PFA) of FCIP are thus in demand to characterize defects in die with these package types. As interconnect metallization schemes become more dense and complex, access to the backside silicon of a functional device also becomes important for fault isolation test purposes. To address these requirements, a detailed PFA flow is described which chronicles the sample preparation methods necessary to isolate a physical defect in the die of an organic-substrate FCIP.


Author(s):  
Sarven Ipek ◽  
David Grosjean

Abstract The application of an individual failure analysis technique rarely provides the failure mechanism. More typically, the results of numerous techniques need to be combined and considered to locate and verify the correct failure mechanism. This paper describes a particular case in which different microscopy techniques (photon emission, laser signal injection, and current imaging) gave clues to the problem, which then needed to be combined with manual probing and a thorough understanding of the circuit to locate the defect. By combining probing of that circuit block with the mapping and emission results, the authors were able to understand the photon emission spots and the laser signal injection microscopy (LSIM) signatures to be effects of the defect. It also helped them narrow down the search for the defect so that LSIM on a small part of the circuit could lead to the actual defect.


Author(s):  
Gwee Hoon Yen ◽  
Ng Kiong Kay

Abstract Today, failure analysis involving flip chip [1] with copper pillar bump packaging technologies would be the major challenges faced by analysts. Most often, handling on the chips after destructive chemical decapsulation is extremely critical as there are several failure analysis steps to be continued such as chip level fault localization, chip micro probing for fault isolation, parallel lapping [2, 3, 4] and passive voltage contrast. Therefore, quality of sample preparation is critical. This paper discussed and demonstrated a quick, reliable and cost effective methodology to decapsulate the thin small leadless (TSLP) flip chip package with copper pillar (CuP) bump interconnect technology.


2018 ◽  
Author(s):  
Lucile C. Teague Sheridan ◽  
Tanya Schaeffer ◽  
Yuting Wei ◽  
Satish Kodali ◽  
Chong Khiam Oh

Abstract It is widely acknowledged that Atomic force microscopy (AFM) methods such as conductive probe AFM (CAFM) and Scanning Capacitance Microscopy (SCM) are valuable tools for semiconductor failure analysis. One of the main advantages of these techniques is the ability to provide localized, die-level fault isolation over an area of several microns much faster than conventional nanoprobing methods. SCM, has advantages over CAFM in that it is not limited to bulk technologies and can be utilized for fault isolation on SOI-based technologies. Herein, we present a case-study of SCM die-level fault isolation on SOI-based FinFET technology at the 14nm node.


Author(s):  
Jason H. Lagar ◽  
Rudolf A. Sia

Abstract Most Wafer Level Chip Scale Package (WLCSP) units returned by customers for failure analysis are mounted on PCB modules with an epoxy underfill coating. The biggest challenge in failure analysis is the sample preparation to remove the WLCSP device from the PCB without inducing any mechanical defect. This includes the removal of the underfill material to enable further electrical verification and fault isolation analysis. This paper discusses the evaluations conducted in establishing the WLCSP demounting process and removal of the epoxy underfill coating. Combinations of different sample preparation techniques and physical failure analysis steps were evaluated. The established process enabled the electrical verification, fault isolation and further destructive analysis of WLCSP customer returns mounted on PCB and with an epoxy underfill coating material. This paper will also showcase some actual full failure analysis of WLCSP customer returns where the established process played a vital role in finding the failure mechanism.


Author(s):  
Yongkai Zhou ◽  
Jie Zhu ◽  
Han Wei Teo ◽  
ACT Quah ◽  
Lei Zhu ◽  
...  

Abstract In this paper, two failure analysis case studies are presented to demonstrate the importance of sample preparation procedures to successful failure analyses. Case study 1 establishes that Palladium (Pd) cannot be used as pre-FIB coating for SiO2 thickness measurement due to the spontaneously Pd silicide formation at the SiO2/Si interface. Platinum (Pt) is thus recommended, in spite of the Pt/SiO2 interface roughness, as the pre-FIB coating in this application. In the second case study, the dual-directional TEM inspection method is applied to characterize the profile of the “invisible” tungsten residue defect. The tungsten residue appears invisible in the planeview specimen due to the low mass-thickness contrast. It is then revealed in the cross-sectional TEM inspection.


Author(s):  
Swaminathan Subramanian ◽  
Khiem Ly ◽  
Tony Chrastecky

Abstract Visualization of dopant related anomalies in integrated circuits is extremely challenging. Cleaving of the die may not be possible in practical failure analysis situations that require extensive electrical fault isolation, where the failing die can be submitted of scanning probe microscopy analysis in various states such as partially depackaged die, backside thinned die, and so on. In advanced technologies, the circuit orientation in the wafer may not align with preferred crystallographic direction for cleaving the silicon or other substrates. In order to overcome these issues, a focused ion beam lift-out based approach for site-specific cross-section sample preparation is developed in this work. A directional mechanical polishing procedure to produce smooth damage-free surface for junction profiling is also implemented. Two failure analysis applications of the sample preparation method to visualize junction anomalies using scanning microwave microscopy are also discussed.


Author(s):  
Ravikumar Venkat Krishnan ◽  
Lua Winson ◽  
Vasanth Somasundaram ◽  
Phoa Angeline ◽  
Pey Kin Leong ◽  
...  

Abstract Short wavelength probing (SWP) uses wavelengths of light shorter than 1100 nm or energies higher than silicon bandgap for laser probing applications. While SWP allows a significant improvement to spatial resolution, there are aberrations to the collected laser probing waveforms which result in difficulties in signal interpretations. In this work, we assess the signals collected through SWP (785 nm) and introduce a photodiode model to explain the observations. We also present a successful case study using 785 nm for failure analysis in sub-20 nm FinFET technology.


2021 ◽  
Author(s):  
Kuang-Tse Ho ◽  
Cheng-Che Li

Abstract This research summarizes failure analysis results about ionimplantation related issues in Si-based power devices, including diode, MOSFET and IGBT. To find out this kind of defects, sample preparation, fault isolation and SCM inspection are critical steps, which will be explained in detail in this paper.


Sign in / Sign up

Export Citation Format

Share Document