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FEM Job Opportunity at Apple

Job Summary

We are looking for a self-motivated individual who is proficient in FEM simulation with multi-year hands-on experience of FEM software ASNSY or ABAQUS. The individual should also be an expert programmer of numerical simulation tools, such as: MatLab and/or Python.

Jie-Hua Zhao's picture

FEM Job Opportunity at Apple

We are looking for a self-motivated individual who is proficient in FEM simulation with multi-year hands-on experience of FEM software ASNSY or ABAQUS. The individual should also be an expert programer of numerical simulation tools, such as Matlab and Python.

Key Qualifications 

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Inter Opportunity at Apple

I am hiring an Engineering Intern this year. The candidates are expected to be graduate students with solid training in mechanics and programming. The starting date is expected to be this summer, however, it can be also earlier. This opening does not sponsor visa application and the candidates should be currently enrolled in US universities and is expected to return to the same school after the internship.  Please email your resume to jhzhao at apple.com.

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Intern Opening at Apple

You will be working on stress simulation of electronic components and sensors with a group of brilliant minds here in Apple’s Headquarters. You are a graduate student with good academic standing majoring in Mechanical Engineering, Engineering Mechanics or similar engineering fields. You are a good programmer and familiar with Python. You must be authorized to work in US. The intern position is open immediately. Send your resume to Jeff Zhao (jhzhao at apple.com).

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Sr. Packaging Mechanical Analyst at Apple

 Sr. Packaging Mechanical Analyst

  • Job Number: 25557504 
  • Santa Clara Valley, California, United States
  • Posted: Jan. 3, 2013
  • Weekly Hours: 40.00

Job Summary

Mechanical engineer working in the central IC packaging group.

Key Qualifications

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Research Position at Texas Instruments (Dallas, Texas)

 
   This is a stress modeling position in TI's research
organization Silicon Technology Development (SiTD). The opening is
immediate and the position is filling very fast. Minimum requirement:
MS degree in the following fields: Mechanical Engineering, Physics,
Materials Science or Engineering Mechanics. PhD degree is preferred. 
Please email your resume to Jie-Hua (Jeff) Zhao at jhzhao@ti.com or
Darvin Edwards at rvin@ti.com. Call Jeff at 972-995-8851 for detail.

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A PROBABILISTIC MECHANICS APPROACH TO DIE CRACKING

Flip-chip plastic ball grid array (FC-PBGA) packages are widely used in high performance components. However, its die back is normally under tensile stress at low temperatures. This paper presents a probabilistic mechanics approach to predict the die failure rate in the FC-PBGA qualification process. The methodology consists of three parts:

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Microstructure-based Stress Modeling of Tin Whisker Growth

Jie-Hua Zhao, Peng Su, Min Ding, Sheila Chopin, and Paul S. Ho

A 3-dimensional finite element method (FEM) model considering the elasticity anisotropy, thermal expansion anisotropy and plasticity of β-Sn is established. The Voronoi diagrams are used to generate the geometric patterns of grains of the Sn coating on Cu leadframes. The crystal orientations are assigned to the Sn grains in the model using the x-ray diffraction (XRD) measurement data of the samples. The model is applied to the Sn-plated package leads under thermal cycling tests. The strain energy density (SED) is calculated for each grain. It is observed that the samples with higher calculated SED are more likely to have longer Sn whiskers and higher whisker density. The FEM model, combined with the XRD measurement of the Sn finish, can be used as an effective indicator of the Sn whisker propensity. This may expedite the qualification process significantly.

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