Electroglas
4090
Provisional entry — research in progress
This page was generated automatically from cited public sources and hasn't completed the full research pass yet. Every specification shown carries its source; more detail is added as research completes.
What it is
General reference — not yet source-verifiedA test and probe system is used to make electrical contact to a semiconductor wafer or die so devices can be measured before later assembly steps. It belongs to wafer-level electrical test equipment rather than front-end process tools that pattern or deposit materials.
How it works
A probe system typically uses a chuck to hold the wafer and a probe card or probe head to contact wafer pads. The chuck moves to bring the wafer into electrical contact with the probes, allowing each die or site to be tested electrically.[4]
In this class of equipment, the wafer is positioned precisely, the probes touch designated contact pads, and test signals are applied and measured through the contact interface. Systems of this kind are also used with thickness and obstruction-sensing approaches to reduce the risk of damaging probe needles during contact.[4]
Where it fits in the process flow
This equipment sits in wafer sort or wafer-level electrical test, after wafers have been fabricated and before singulation and downstream packaging. It is used to separate acceptable dies from defective dies at an early inspection point.[4]
Applications
The class is used in wafer sort for device screening and for checking electrical properties before devices move to later assembly steps.[4]
What do the numbers mean?
Configuration & options2
Vintage & configurations
Documented models & variants
| Designation | Generation | Vintage | Changes | Source |
|---|---|---|---|---|
| 4090+ Prober | — | — | — | Equipment inventory listing[1] |
| Electroglas 4090 with ETS 200 Tester | — | — | Configured with an ETS 200 Tester | Equipment inventory listing[2] |
| Electroglas 4090 with LTX / Credence ASL 1000 Tester | — | — | Configured with an LTX / Credence ASL 1000 Tester | Equipment inventory listing[3] |
Where are the manuals?
Generated from public-source data on file. Enter your email to access — nothing is published; details are routed privately.
Not publicly documented
Field notes
No research found yet — worked with this tool? Share what you know.
Frequently asked questions
What does this type of system do at the wafer stage?
It electrically tests wafers by bringing probes into contact with wafer pads so die can be evaluated before singulation and packaging.[4]
What mechanical elements are typical in this class of equipment?
The typical arrangement includes a chuck that supports the wafer and a probe card or probe head positioned above it.[4]
Why are obstruction-sensing or thickness-sensing methods used with probe systems?
They help avoid damaging probe pins when wafer thickness varies or when particles create high spots that can interfere with contact.[4]
Not publicly documented
The following facts about the 4090 are absent from this record as of this revision. First-hand knowledge or a citation closes a gap; every submission is reviewed before publication.
Fewer than 3 independently cited specifications for the 4090 are on record; the remainder await public documentation.
Answerable by: an OEM datasheet, a cleanroom equipment inventory, or an engineer who operated or installed it
No publicly documented production dates or lifecycle milestones (introduction, end of production, EOL) for the 4090 are on record.
Answerable by: OEM historical records or a trade-press announcement
The control-system platform and OS era of the 4090 are not on record.
Answerable by: an engineer who operated it or OEM installation records
No publicly documented failure modes or field errata for the 4090 are on record.
Answerable by: a field service engineer, process engineer, or maintenance technician
The process node or technology generation of the 4090 is not on record.
Answerable by: an OEM datasheet or a fab qualification report
No research found yet — worked with this tool? Share what you know.
Sources & citations
Sources (7)Every fact above is drawn from these public sources
- [1]Inventory photo
- [2]inventory listing
- [3]inventory listing
- [4]US20070046311A1 - Systems and methods for sensing obstructions associated with electrical testing of microfeature workpieces - Google Patents — patents.google.compatents.google.com
- [5]Equipment inventory listing
- [6]Electroglas, Inc. products: the horizon 4090 — electroglas.com (Oct 6, 1999)web.archive.org
- [7]ELECTROGLAS INC Form 10-K (1999) — SEC EDGAR — sec.gov (Mar 12, 1999)sec.gov
Last updated Jul 29, 2026.
