Sample Preparation for High Numerical Aperture Solid Immersion Lens Laser Imaging

2014 ◽  
Author(s):  
M.S. Wei ◽  
H.B. Chong ◽  
S.H. Lim ◽  
C. Richardson
Keyword(s):  
Sample Preparation ◽  
Focal Length ◽  
Numerical Aperture ◽  
Fault Isolation ◽  
Numerical Control ◽  
Thickness Variation ◽  
Solid Immersion Lens ◽  
Laser Imaging ◽  
High Numerical Aperture ◽  
Silicon Thickness

Abstract High resolution laser imaging, using high numerical aperture (NA) solid immersion lens (SIL) for backside fault isolation imposes stringent sample preparation requirements; as a result of the short focal length of SIL, a die must be thinned to a targeted thickness with less than a ±5 μm silicon thickness variation across the entire die. Flip chip packaged dice suffer from warpage due to various package sizes and substrate thicknesses. Such broad spectrums of part geometries pose a great challenge to meet such silicon planarity requirements. As relaxation of the packaged silicon during polishing causes the warpage profile to change dynamically and unpredictably throughout the thinning process, it has become an added challenge to meet the stringent sample preparation requirements. To overcome the stochastic nature of this problem, a two-step polishing recipe consisting of computer numerical control (CNC) mechanical milling and polishing processes has been developed to achieve sufficient silicon thickness uniformity to enable SIL imaging across an entire silicon chip as large as approximately 20 mm x 15 mm.

Two-Photon Absorption Laser Assisted Device Alteration Using 1340nm CW Laser: Critical Timing Fault Isolation & Localization for 32nm MPU and Beyond

2010 ◽  
Author(s):  
Baohua Niu ◽  
Pat Pardy ◽  
Joe Davis ◽  
Mel Ortega ◽  
Travis Eiles
Keyword(s):  
High Power ◽  
Continuous Wave ◽  
Numerical Aperture ◽  
Fault Isolation ◽  
Photon Absorption ◽  
Solid Immersion Lens ◽  
Two Photon Absorption ◽  
Two Photon ◽  
Critical Timing ◽  
Power Densities

Abstract In this paper, we report on the first observation and study of two-photon absorption (TPA) based laser assisted device alteration (LADA) using a continuous-wave (CW) 1340nm laser. The study was conducted using LADA systems equipped with high numerical aperture (NA) liquid and solid immersion lens objectives on Intel’s 45 nm and 32 nm multiprocessor units (MPU) and test chips. The power densities achievable using these lenses are similar to those reported in the literature for TPA in silicon of CW 1455nm light [1]. We show that the induced photocurrent has a quadratic dependence on the input laser power, a key indicator of two-photon phenomenon. Our results imply that even when using 1340nm wavelength CW lasers, there is a potential for laser invasiveness with the high power densities achievable using high NA objectives. Laser induced damage of the DUT is also a possibility at these high power densities, particularly with the solid immersion lens (SIL). However, we show that the DUT damage threshold can be increased by reducing the DUT’s temperature. Finally, we present results demonstrating a >40% improvement in localization of critical timing faults using TPA based LADA, when compared to traditional 1064nm wavelength (single-photon absorption) LADA.

Targeted Silicon Ultra-Thinning by Contour Milling for Advanced Fault Isolation

2019 ◽  
Author(s):  
W. S. Teo ◽  
M.S. Wei ◽  
V. Narang ◽  
C. L. Gan ◽  
C. Richardson ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Sample Preparation ◽  
Failure Analysis ◽  
Fault Isolation ◽  
Thin Sample ◽  
Electrical Failure ◽  
Contour Maps ◽  
Area Of Interest ◽  
Silicon Thickness ◽  
Thermal Stability Of

Abstract In this paper, we present methods for targeted silicon thinning by contour milling to overcome challenges associated with thinning large devices to under 5 µm remaining silicon thickness. Implementation of these techniques are expected to improve the yield of ultra-thin sample preparation and thermal stability of the device through electrical failure analysis for subsequent physical failure analysis. Using a computer numerical controlled milling system, the natural device bow is exploited to thin a specified area of interest by stage tilting before 2D milling. To target a larger area of interests, contour maps are rigged to thin an area preferentially while remaining compatible with existing workflows. Electrical testing have found improved thermal stability of the locally thinned samples over globally thinned samples.

scholarly journals From Spheric to Aspheric Solid Polymer Lenses: A Review

2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Kuo-Yung Hung ◽  
Po-Jen Hsiao ◽  
Fang-Gang Tseng ◽  
Miao-Chin Wei
Keyword(s):  
Data Storage ◽  
Focal Length ◽  
Current Trend ◽  
Numerical Aperture ◽  
Optical Data Storage ◽  
Polymer Materials ◽  
Solid Polymer ◽  
Optical Data ◽  
External Control ◽  
High Numerical Aperture

This paper presents a new approach in the use of MEMS technology to fabricate micro-optofluidic polymer solid lenses in order to achieve the desired profile, focal length, numerical aperture, and spot size. The resulting polymer solid lenses can be applied in optical data storage systems, imaging systems, and automated optical inspection systems. In order to meet the various needs of different applications, polymer solid lenses may have a spherical or aspherical shape. The method of fabricating polymer solid lenses is different from methods used to fabricate tunable lenses with variable focal length or needing an external control system to change the lens geometry. The current trend in polymer solid lenses is toward the fabrication of microlenses with a high numerical aperture, small clear aperture (<2 mm), and high transmittance. In this paper we focus on the use of thermal energy and electrostatic force in shaping the lens profile, including both spherical and aspherical lenses. In addition, the paper discusses how to fabricate a lens with a high numerical aperture of 0.6 using MEMS and also compares the optical characteristics of polymer lens materials, including SU-8, Norland Optical Adhesive (NOA), and cyclic olefin copolymer (COC). Finally, new concepts and applications related to micro-optofluidic lenses and polymer materials are also discussed.

A high numerical aperture solid immersion lens magneto-optical recording system

1999 ◽  
Vol 35 (5) ◽  
pp. 3100-3105 ◽  
Author(s):  
A. Chekanov ◽  
M. Birukawa ◽  
Y. Itoh ◽  
T. Suzuki
Keyword(s):  
Numerical Aperture ◽  
Optical Recording ◽  
Recording System ◽  
Solid Immersion Lens ◽  
High Numerical Aperture

Sample Preparation Techniques for Reduced Lateral Heat Distribution and Implications for Non-IR Probing on Integrated Circuits

2017 ◽  
Author(s):  
Matthew M. Mulholland ◽  
Vladimir V. Vlasyuk ◽  
Robert P. Wadell ◽  
Imran Khan ◽  
Nathan J. Bakken
Keyword(s):  
Sample Preparation ◽  
Product Life Cycle ◽  
Junction Temperature ◽  
Visible Range ◽  
Heat Distribution ◽  
Solid Immersion Lens ◽  
Optical Probing ◽  
Silicon Thickness ◽  
Preparation Techniques ◽  
Lateral Heat

Abstract Validation techniques on packaged integrated circuit (IC) samples positively impact time to market (TTM) by saving considerable fabrication modification turnaround time and costs. The validation techniques are typically done by working through the backside of the chip. These validation and debug techniques, such as optical probing, use the Solid Immersion Lens (SIL) for imaging and data collection. Solid Immersion Lens based near infrared (NIR) optical probing systems have been an integral function in the product life cycle enabling a fast, reliable, and low defect product to market. For the SIL configuration, the remaining silicon thickness (RST) target is specified to be 50 +/- 5um. The sample preparation tools and techniques to accomplish this have been fully developed and matured enough to provide this specification for all segment form factors. This silicon thickness is also within a sustainable thermal envelope at certain power densities during debug electrical testing and validation. As we move into the next generation of optical probing debug in the visible range, increasing resolution further, new sample preparation methods need to be developed. There are a number of different strategies and techniques to prepare the sample, while also enabling efficient heat transfer. This paper will detail some of the sample preparation techniques as a function of silicon thickness and aspect ratio. These final geometries will then be characterized thermally by investigating lateral heat distribution and junction temperature within the silicon Region of Interest (ROI). Finally, based on this sample preparation and thermal study, implications around debug techniques for optical probing will be discussed.

Sign in / Sign up

Export Citation Format

Share Document