Signatone
SP4
The Signatone SP4 is a four point probe head used for resistivity measurements. The SP4 is made from mold-injected Delrin and designed for room temperature operation. The SP4 has four probe tips in a straight line with selectable spacings and spring pressures.[1][2]
What it is
The Signatone SP4 is a four point probe head for resistivity testing. The SP4 is made from mold injected Delrin and is designed for use at room temperatures.[1]
How it works
The SP4 family supports multiple probe tip spacings, spring pressures, tip materials, and optional blunt tip radii. The available spacing options are 40 mils, 50 mils, and 62.5 mils between probe tips, and the available spring pressure options are 45 grams, 85 grams, and 180 grams per tip.[1]
The SP4 family offers osmium or tungsten carbide probe tip materials. The standard probe tip size is 1.6 mil diameter, and optional blunt tip radii of R=.005 and R=.010 correspond to 5 mil and 10 mil diameter tips.[1]
Applications
The SP4 is used for resistivity measurement and resistivity probing. The SP4 is also used for silicon wafer probing applications.[1][2]
The SP4 family is available with osmium tips for gallium arsenide wafers or when contact resistance is a concern. The SP4 family is also available with tungsten carbide tips for harder wear resistance.[1]
- Resistivity measurement
- Resistivity probing applications
- Silicon wafer probing applications
What do the numbers mean?
Vacuum & pumping2
Configuration & options14
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 type of tool is the SP4?
The SP4 is a Signatone four point probe head for resistivity measurement.[1]
What material is the SP4 body made from?
The SP4 is made from mold injected Delrin.[1]
What operating temperature is the SP4 designed for?
The SP4 is designed for use at room temperatures.[1]
What probe tip spacings are available for the SP4 family?
The SP4 family offers 40 mil, 50 mil, and 62.5 mil probe tip spacing.[1]
What tip materials are available for the SP4 family?
The SP4 family offers osmium and tungsten carbide probe tips.[1]
Not publicly documented
The following facts about the SP4 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 SP4 are on record.
Answerable by: OEM historical records or a trade-press announcement
No publicly documented variants, configuration options, or revision breakpoints of the SP4 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 SP4 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 SP4 are on record.
Answerable by: a field service engineer, process engineer, or maintenance technician
The process node or technology generation of the SP4 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 (2)Every fact above is drawn from these public sources
- [1]web.archive.org — web.archive.orgweb.archive.org
- [2]SP4 — Signatone | Specs, Sourcing & Service | Waferpedia — waferpedia.comwaferpedia.com
Last updated Oct 6, 2026.
