Packaging Mechanical Engineer

DensityAI•Mountain View, CA

4d•$200,000 - $275,000

About The Position

Own the thermo-mechanical design of the advanced packages our AI accelerator silicon ships in. A multi-die 2.5D package is a stack of materials that all want to expand at different rates, under a lid, under load, cycling through hundreds of watts — and your job is to make it stay flat, stay bonded, and stay intact. You'll model warpage and stress through reflow and assembly, design the lid, stiffener, underfill and TIM stack that controls them, set the mechanical rules our OSATs build to, and own the socket and load mechanics where the package meets the cooling solution. You'll correlate every model against real measurement, and you'll be the person who knows whether a design will survive the assembly line before it gets there.

Requirements

Exceptional abilities in thermo-mechanical analysis of semiconductor packages: warpage prediction and control, die and solder-joint stress, delamination and interfacial fracture risk, and material and structural tradeoffs
8+ years of packaging mechanical experience on high-performance designs, including 2.5D / 3D and multi-die packages (CoWoS, EMIB, InFO, fan-out, or equivalent) and HBM-bearing assemblies
Hands-on with industry-standard FEA tools (Ansys Mechanical, Abaqus, or equivalent) and strong materials knowledge across underfills, mold compounds, substrates, TIMs, and lid materials
Demonstrated ability to work closely with packaging, thermal, reliability, board, and OSAT partners to converge mechanical designs and sign them off against JEDEC and IPC standards
Work authorization is required at start; we provide immigration support to secure or transfer status.

Responsibilities

Own thermo-mechanical modeling and FEA for multi-die packages; warpage across reflow and assembly, die and interconnect stress, CTE mismatch, and structural response under thermal and mechanical load
Own package mechanical design; lid and heat spreader, stiffener, underfill and mold compound selection, and TIM specification and bondline control at the package-to-cooling interface
Drive assembly process mechanics and mechanical design rules with OSATs and substrate suppliers, and own socket and load-frame mechanics for high-force accelerator sockets
Correlate models to measurement (shadow moire, strain gauge, DIC) and drive DOEs that close the gap between simulation and silicon
Use and develop AI assisted tool flows to accelerate mechanical modeling and signoff timelines