{"id":309718,"url":"https://alion.io/job/lightmatter-sr-staff-thermo-mechanical-engineer","title":"Sr. Staff Thermo-Mechanical Engineer","company":{"id":16141,"name":"Lightmatter","domain":"lightmatter.co","url":"https://alion.io/company/lightmatter-co","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Greenhouse","truth_index":{"grade":"B","score":81,"open_postings":21,"ghost_share":0,"stale_share":0.762,"repost_share":0,"time_to_fill_p50_days":43,"computed_at":"2026-10-23T05:54:15Z"}},"role":"Industrial Engineering","role_family":"Industrial Engineering","seniority":"staff","employment_type":null,"work_mode":"hybrid","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Mountain View, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":169000,"max":244000,"currency":"USD","period":"year","gross":null,"usd_annual":244000},"salary_estimate":null,"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":true,"technologies":[{"name":"Abaqus","optional":false},{"name":"ANSYS","optional":false},{"name":"HPC","optional":false},{"name":"MATLAB","optional":false},{"name":"Python","optional":false},{"name":"JMP","optional":true}],"status":"live","first_seen_at":"2026-08-09T20:37:04Z","employer_posted_date":"2026-08-25","last_verified_at":"2026-10-23T21:32:10Z","board_verified":true,"closed_at":null,"days_open":75,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":75},"description":"Lightmatter is leading the revolution in AI data center infrastructure, enabling the next giant leaps in human progress. The company invented the world’s first 3D-stacked photonics engine, Passage™, capable of connecting thousands to millions of processors at the speed of light in extreme-scale data centers for the most advanced AI and HPC workloads.\nLightmatter raised $400 million in its Series D round, reaching a valuation of $4.4 billion. We will continue to accelerate the development of data center photonics and grow every department at Lightmatter!\nIf you're passionate about tackling complex challenges, making an impact, and being an expert in your craft, join our team of brilliant scientists, engineers, and accomplished industry leaders.\nLightmatter is (re)inventing the future of computing with light!\nIn this role, you will work on leading-edge packaging technologies to enable AI architectures that will set new industry standards regarding compute power, performance, and efficiency.\nYou will collaborate with the packaging team to carry out the required structural analysis for packaging technologies under consideration, identify key failure modes under product use conditions, and run appropriate parametric studies to influence product and package design upstream. You will focus on thermo-mechanical analysis and characterization of advanced photonics packaging technologies, including 3D stack development, heterogeneous integration of lasers and novel fiber attach methods, to define design, material, and process solutions that successfully meet assembly and reliability requirements. The results of your work will lead to advanced package designs that meet power dissipation, optical, assembly, and reliability requirements while delivering a system-level solution for leading-edge products in the AI market.\nResponsibilities: \nServe as the technical authority for thermo-mechanical simulation within the packaging organization, setting standards for model fidelity, validation methodology, and documentation practices adopted across the team.\nIdentify capability gaps in simulation tooling, characterization methods, or material databases and champion fundamental investigations that strengthen the team's long-term technical foundation.\nDevelop finite element stress, warpage, and assembly process models for wafer-level and unit-level photonic packaging, identifying design, process, and material parameters to mitigate failure modes and optimize yield.\nPerform analysis to identify key reliability risks under product use conditions and drive appropriate design and material solutions to improve product mechanical integrity.\nConduct multi-physics simulations including solder collapse modeling for bump architecture definition and thermal-structural analysis for packaging stress to meet thermal, electrical, and optical requirements.\nDevelop analytical or semi-empirical models for quick turn assessments for new product concepts.\nDrive characterization and validation of mechanical designs and electronic assemblies through lab-scale prototyping and vendor-initiated experiments, closing the loop between simulation predictions and physical hardware.\nDevelop Python and MATLAB automation frameworks to scale simulation throughput and establish repeatable, high-efficiency modeling workflows.\nSummarize and communicate findings and recommendations with authority to key stakeholders across Lightmatter, suppliers, and customers.\nWrite reports and document methodologies that serve as the technical foundation for the packaging team.\nRequired Qualifications:\nMS or PhD in Mechanical Engineering, Material Science, or a related engineering field.\nDeep expertise in finite element analysis using commercial tools such as Ansys, Abaqus, or equivalent, with demonstrated ability to develop and validate models for complex multi-material assemblies.\nHands-on experience with multi-physics simulation including thermal-structural coupling, solder joint fatigue modeling, and warpage analysis.\nStrong understanding of semiconductor packaging failure modes including solder fatigue, delamination, CTE mismatch-driven stress, and underfill cracking under thermal cycling conditions.\nExperience with wafer-level and unit-level assembly processes including flip-chip, BGA, and advanced 3D packaging architectures.\nProficiency in Python and/or MATLAB for simulation automation, data analysis, and scripting.\nDemonstrated ability to develop analytical or semi-empirical models for first-order engineering assessments.\nExperience driving characterization and validation programs through internal prototyping and external vendor collaboration.\nPreferred Qualifications: \nProven track record of communicating complex technical findings to cross-functional audiences including design, process, and product engineering teams.\nStrong technical writing skills with experience producing simulation reports, design guidelines, and methodology documentation.\nExperience with photonic packaging technologies including silicon photonics, co-packaged optics, fiber attach, or heterogeneous integration of laser devices.\nFamiliarity with optical packaging reliability requirements and the intersection of thermo-mechanical performance with optical alignment stability.\nAbility to work independently and manage multiple projects with minimal supervision.\nExperience with statistical analysis tools and techniques such as DOE and JMP.\nStrong creative thinking skills with the ability to solve problems quickly.\nWe offer competitive compensation. The base salary range for this role determined based on location, experience, educational background, and market data.\nSalary Range: total compensation goes beyond base salary, it also includes a new hire equity grant, annual performance-based equity, and other rewards that recognize your impact and contribution.\n$169,000—$244,000 USD\nBenefits\nComprehensive Health Care Plan (Medical, Dental & Vision)\nRetirement Savings Matching Program\nLife Insurance (Basic, Voluntary & AD&D)\nGenerous Time Off (Vacation, Sick & Public Holidays)\nPaid Family Leave\nShort Term & Long Term Disability\nTraining & Development\nCommuter Benefits\nFlexible, hybrid workplace model\nEquity grants (applicable to full-time employees)\nBenefits eligibility may vary depending on your employment status and location. Lightmatter recruits, employs, trains, compensates, and promotes regardless of race, religion, color, national origin, sex, disability, age, veteran status, and other protected status as required by applicable law.\nExport Control\nCandidates should have capacity to comply with the federally mandated requirements of U.S. export control laws.","description_format":"text","description_chars":6682,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"master","optional":false},"security_clearance":false,"languages":[]},"benefits":["Equity","Life insurance","Parental leave"],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["AI Chips & Accelerators","Optics & Photonic Components"],"lifecycle":[{"event":"open","at":"2026-09-05T15:42:26Z"}],"visa":[{"country":"US","licensed_sponsor":true,"evidence":"H-1B filings in 12 months: 27 · green card filings: 1","filings_12m":27,"filings_prev_12m":14,"green_card_filings_12m":1,"median_offered_wage_usd":177679,"route":null,"cap_exempt":false,"checked_at":"2026-10-15T11:24:14+00:00","sources":["US Department of Labor: LCA disclosure data (H-1B, H-1B1, E-3)","US Department of Labor: PERM disclosure data (green cards)"],"filings_for_role_12m":0}],"liveness":{"score":19,"band":"cold","label":"Long shot","p_open":1,"p_active":0.524,"p_room":0.36,"age_days":74,"expected_fill_days":43,"reasons":["conf:3","stale_co","velocity","win:tail","crowd:"],"computed_at":"2026-10-23T05:54:15Z"},"pay":{"stated_usd_annual":244000,"is_top_pay":true},"html_url":"https://alion.io/job/lightmatter-sr-staff-thermo-mechanical-engineer","json_url":"https://alion.io/job/lightmatter-sr-staff-thermo-mechanical-engineer.json","meta":{"generated_at":"2026-10-23T23:47:23Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":7400,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-24T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":16141},"rest":"https://alion.io/mcp/rest/get_company?id=16141"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Flightmatter-sr-staff-thermo-mechanical-engineer"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Flightmatter-sr-staff-thermo-mechanical-engineer"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Flightmatter-sr-staff-thermo-mechanical-engineer"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/lightmatter-sr-staff-thermo-mechanical-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Flightmatter-sr-staff-thermo-mechanical-engineer"}]}