Comparative Reliability Study of Au Wire Bond Contacts on Al Metallization vs. over Pad Metallization

2016 ◽  
Author(s):  
R. Klengel ◽  
J. Schischka ◽  
L. Berthold ◽  
S. Klengel
Keyword(s):  
Reliability Study ◽  
Wire Bond ◽  
Al Metallization

IC Bond Pad Structural Study by “Ripple Effect”

2011 ◽  
Vol 2011 (1) ◽  
pp. 000491-000501
Author(s):  
Jose Martinez ◽  
Cesar Salas ◽  
Marco Salas ◽  
Jason Schofield ◽  
Steven Sheffield ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Structural Reliability ◽  
Dielectric Film ◽  
Ripple Effect ◽  
Dielectric Body ◽  
Uniform Deformation ◽  
Wire Bond ◽  
Metal Plates ◽  
Similar Appearance ◽  
Al Metallization

IC bond pad structural reliability is studied for a variety of experimental pad designs in a 0.18um technology, having patterned metallization to simulate bond-over-active-circuitry (BOAC) situations in top-metal-minus-one and below. Underlying films deformation after wire bond is studied by optical microscopy after removal of the pad Al, with additional measurements by FIB. Pad designs in this study are rated for robustness to cracking according to an optical “ripple effect” deformation scale. “Ripple” is so named because it has a similar appearance to water ripples. It is due to non-uniform deformation in the underlying Al film(s) in the pad structure. Though the Al material is fully constrained within the SiO2 dielectric body, it is able to migrate plastically into local “hills and valleys” during bonding stress, with the top dielectric film bending in conformance. Cracks can then initiate in the undulating upper dielectric when its tensile strength is exceeded. “Ripple” in these pads is seen to vary depending upon the underlying metallization pattern and density as well as with wire bonding stress, for a fixed pad Al thickness. Traditional-style Al metallization pad structures with full metal plates are least robust, being the most prone to high “ripple” and cracks. Other pad structures more indicative of BOAC designs show varying degrees of improved robustness to cracking as shown by decreasing “ripple”. Results show that significant improvements in pad robustness to cracking are feasible in BOAC designs which include top-metal-minus-one routing in Al-metallization technologies, while providing increased process margin in wire bond, permitting efficient use of die area without extra processing or new issues.

Bond Over Active Circuitry Design for Reliability

2011 ◽  
Vol 2011 (1) ◽  
pp. 000249-000257
Author(s):  
Stevan Hunter ◽  
Jose Martinez ◽  
Cesar Salas ◽  
Marco Salas ◽  
Jason Schofield ◽  
...  
Keyword(s):  
Thin Films ◽  
Lower Cost ◽  
Layout Design ◽  
Free Form ◽  
Design Rules ◽  
Wire Bond ◽  
Interconnect Design ◽  
Wafer Processing ◽  
Al Metallization ◽  
Metal Layers

This paper discusses layout design rules for successful Cu wire bond-over-active-circuitry (BOAC) in 0.18 micron and other IC technologies having Al metallization interconnects (two-level metal and up) in SiO2 dielectric, with W vias. The resulting bond pad structures effectively address BOAC pad reliability concerns, permitting Au or Cu wire bonding on relatively thin top metal. Cu wire bond is attractive on BOAC designs for lower cost than Au wire, while improving the thermal capability of the product. But Cu wire bond has presented even more challenges than Au wire bond due to higher stress to the pads during bonding, typically leading to increases in underlying films deformation and cracking. The new BOAC pad layout rules are based on the physical thin films principles, substantiated and refined through analysis of a large volume of experimental and product qualification data in various IC technologies. Interconnect layout beneath pads which follows the BOAC design rules creates more robust bond pad structures, preventing Al films deformation while strengthening the dielectric against cracking, and permitting free-form Si device design beneath. Substantial freedom in interconnect design is permitted in all metal layers beneath the pad, but the rules for top via and top-metal-minus-one layers are more restrictive than the rest. The BOAC design rules do not require any changes in wafer processing, they do not prevent the adding of redistribution or other layers for solder bumping or the like, but they do enable smaller die size and less expensive wire bond without jeopardizing bonding reliability.

Validity and Reliability Study of the Strength Self-Efficacy Scale

2010 ◽  
Author(s):  
Ran Zhao ◽  
Chia-Lin Tsai ◽  
Adipat Chaichanasakul ◽  
Lisa Y. Flores ◽  
Shane J. Lopez
Keyword(s):  
Self Efficacy ◽  
Validity And Reliability ◽  
Reliability Study

Reliability Study on Control Unit of Metro Train Auxiliary Inverter Based on Improved Monte Carlo Algorithm

CICTP 2017 ◽  
2018 ◽  
Author(s):  
Ying Ji ◽  
Xiaobo Li ◽  
Hao Wu ◽  
Pengfei Cai
Keyword(s):  
Monte Carlo ◽  
Control Unit ◽  
Monte Carlo Algorithm ◽  
Reliability Study

Development of Inquiry Based Teaching Self-Efficacy Scale for STEM+S Education: Validity and Reliability Study

2018 ◽  
Vol 10 (3) ◽  
Author(s):  
İbrahim Yıldırım ◽  
Mehmet Başaran ◽  
Eyüp Cücük ◽  
Erhan Yokuş
Keyword(s):  
Self Efficacy ◽  
Validity And Reliability ◽  
Reliability Study

Adlerian Life Style: A Reliability Study Of The Lifestyle Scale

1992 ◽  
Author(s):  
Joseph E. Meinecke
Keyword(s):  
Life Style ◽  
Reliability Study ◽  
Adlerian Life Style

Failure Analysis of Short Faults on Advanced Wire-Bond and Flip-Chip Packages with Scanning SQUID Microscopy

2004 ◽  
Author(s):  
Steve K. Hsiung ◽  
Kevan V. Tan ◽  
Andrew J. Komrowski ◽  
Daniel J. D. Sullivan ◽  
Jan Gaudestad
Keyword(s):  
Magnetic Fields ◽  
Integrated Circuits ◽  
Quantum Interference ◽  
Flip Chip ◽  
Infrared Emission ◽  
Fault Analysis ◽  
Wire Bond ◽  
Overlay Design ◽  
Scanning Squid ◽  
Metal Layers

Abstract Scanning SQUID (Superconducting Quantum Interference Device) Microscopy, known as SSM, is a non-destructive technique that detects magnetic fields in Integrated Circuits (IC). The magnetic field, when converted to current density via Fast Fourier Transform (FFT), is particularly useful to detect shorts and high resistance (HR) defects. A short between two wires or layers will cause the current to diverge from the path the designer intended. An analyst can see where the current is not matching the design, thereby easily localizing the fault. Many defects occur between or under metal layers that make it impossible using visible light or infrared emission detecting equipment to locate the defect. SSM is the only tool that can detect signals from defects under metal layers, since magnetic fields are not affected by them. New analysis software makes it possible for the analyst to overlay design layouts, such as CAD Knights, directly onto the current paths found by the SSM. In this paper, we present four case studies where SSM successfully localized short faults in advanced wire-bond and flip-chip packages after other fault analysis methods failed to locate the defects.

Interrater reliability of a method to assess hypothalamic involvement in pediatric adamantinomatous craniopharyngioma

2020 ◽  
Vol 25 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Ros Whelan ◽  
Eric Prince ◽  
David M. Mirsky ◽  
Robert Naftel ◽  
Aashim Bhatia ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Brain Tumors ◽  
Interrater Reliability ◽  
Statistical Evaluation ◽  
Grading System ◽  
Reliability Study ◽  
Postoperative Mri ◽  
Mri Scans ◽  
Adamantinomatous Craniopharyngioma

OBJECTIVEPediatric adamantinomatous craniopharyngiomas (ACPs) are histologically benign brain tumors that confer significant neuroendocrine morbidity. Previous studies have demonstrated that injury to the hypothalamus is associated with worsened quality of life and a shorter lifespan. This insight helps many surgeons define the goals of surgery for patients with ACP. Puget and colleagues proposed a 3-tiered preoperative and postoperative grading system based on the degree of hypothalamic involvement identified on MRI. In a prospective cohort from their institution, the authors found that use of the system to guide operative goals was associated with decreased morbidity. To date, however, the Puget system has not been externally validated. Here, the authors present an interrater reliability study that assesses the generalizability of this system for surgeons planning initial operative intervention for children with craniopharyngiomas.METHODSA panel of 6 experts, consisting of pediatric neurosurgeons and pediatric neuroradiologists, graded 30 preoperative and postoperative MRI scans according to the Puget system. Interrater reliability was calculated using Fleiss’ κ and Krippendorff’s α statistics.RESULTSInterrater reliability in the preoperative context demonstrated moderate agreement (κ = 0.50, α = 0.51). Interrater reliability in the postoperative context was 0.27 for both methods of statistical evaluation.CONCLUSIONSInterrater reliability for the system as defined is moderate. Slight refinements of the Puget MRI grading system, such as collapsing the 3 grades into 2, may improve its reliability, making the system more generalizable.

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