Disco
841 Back
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.
The Disco 841 (also designated DFG 841) is a back grinder used for in-feed grinding of semiconductor wafers. The Disco 841 handles wafers from 4 to 8 inches in diameter. The Disco 841 features two independently adjustable spindles, a robot arm for same-cassette return, and achieves planarity accuracy of 0.0015 mm within the wafer.[1][2]
What it is
The Disco 841, also designated Disco DFG 841, is a back grinder used in semiconductor wafer thinning. The Disco 841 back grinder handles wafers from 4 to 8 inches in diameter. The system uses an 8-inch diamond grinding wheel. The DFG 841 complies with the EC’s CE marking and is based on the SEMI S2-93 safety standard.[3][4][1][2]
How it works
The Disco DFG 841 uses in-feed grinding with wafer rotation. The machine has two independently adjustable spindles with a speed range of 1000 to 7000 rpm. The vertical stroke of the spindles is 110 mm. The system features a porous chuck table with a vacuum chuck to hold the wafer during grinding. The robot arm vacuum ensures that thin-ground wafers, which are prone to warping, are corrected to the required flatness for trouble-free handling. The DFG 841 has two cassettes for loading and unloading. The planarity accuracy within a wafer is 0.0015 mm.[1][2]
What do the numbers mean?
Power & electrical1
Vacuum & pumping3
Wafer handling4
Dimensions & facilities1
Configuration & options5
What does it need to run?
Site utility requirements, footprint, and infrastructure needed to install and operate this tool. Sourced from public records.
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
Not publicly documented
The following facts about the 841 Back are absent from this record as of this revision. First-hand knowledge or a citation closes a gap; every submission is reviewed before publication.
No publicly documented production dates or lifecycle milestones (introduction, end of production, EOL) for the 841 Back are on record.
Answerable by: OEM historical records or a trade-press announcement
No publicly documented variants, configuration options, or revision breakpoints of the 841 Back are on record.
Answerable by: an OEM product catalog or an engineer who ordered or specified the tool
The control-system platform and OS era of the 841 Back 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 841 Back are on record.
Answerable by: a field service engineer, process engineer, or maintenance technician
The process node or technology generation of the 841 Back 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 (4)Every fact above is drawn from these public sources
- [1]s3-alliance.com — s3-alliance.coms3-alliance.com
- [2]DISCO DFG 840/841 Grinder — s3-alliance.coms3-alliance.com
- [3]Equipment inventory listing
- [4]Disco DFG 841 Back Grinder for sale — fabsurplus.comfabsurplus.com
Last updated Sep 1, 2026.
