Disco
840
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
The Disco 840, also referred to as the DFG 840, is a grinder with two independently adjustable spindles and two rotary chuck tables. The system includes a robot arm that uses vacuum to handle thin wafers prone to warping. The machine accommodates wafers with diameters from four to eight inches. The planarity accuracy across a wafer is 0.0015 millimeters. The spindle speed is adjustable from 1000 to 7000 rpm. The vertical stroke of the spindles is 110 millimeters. The chuck table is porous and uses vacuum, and the grinding wheel diameter is eight inches. The system has two cassettes for loading and unloading wafers.[1][3][2]
How it works
The Disco 840 uses in-feed grinding with wafer rotation. The two spindles are independently adjustable, allowing separate coarse and fine grinding steps. The porous chuck table provides vacuum hold for the wafer. The grinding wheel uses an eight-inch diameter diamond wheel. The robot arm vacuum ensures flatness correction for warped wafers. The machine offers a same-cassette return function, meaning a wafer can be returned to its original cassette after processing.[1][3]
Applications
What do the numbers mean?
Power & electrical1
Vacuum & pumping1
Wafer handling3
Dimensions & facilities2
Configuration & options6
Vintage & configurations
Documented models & variants
| Designation | Generation | Vintage | Changes | Source |
|---|---|---|---|---|
| DFG841 | — | — | Complies with EC’s CE marking; based on SEMI S2-93 | s3-alliance.com[1] |
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
What wafer diameters can the Disco 840 process?
The Disco 840 handles wafers with diameters from four to eight inches.[1][3]
What is the planarity accuracy achievable with the Disco 840?
The planarity accuracy within a wafer is 0.0015 millimeters.[1][3]
Not publicly documented
The following facts about the 840 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 840 are on record.
Answerable by: OEM historical records or a trade-press announcement
The control-system platform and OS era of the 840 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 840 are on record.
Answerable by: a field service engineer, process engineer, or maintenance technician
The process node or technology generation of the 840 is not on record.
Answerable by: an OEM datasheet or a fab qualification report
No publicly documented compatible parts, consumables, or accessories for the 840 are on record.
Answerable by: an OEM parts catalog or a service engineer
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]waferpedia.com — waferpedia.comwaferpedia.com
- [3]DISCO DFG 840/841 Grinder — s3-alliance.coms3-alliance.com
- [4]Equipment inventory listing
Last updated Sep 27, 2026.
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