HPSI - Semi-insulating SiC Substrates
Wolfspeed is transitioning to a new wafer scribe format based upon SEMI specification M12-0706. This conversion, which is projected to be fully integrated in 2022, brings several improvements. The M12-based scribe will be positioned upright when the major flat or notch is oriented up, making the scribe easier to read when the wafers are loaded into cassettes. The new format includes a wafer supplier identification code, validating the wafer’s authenticity. It also includes a checksum, which is an error-detection method that prevents OCR mis-read errors and reduces the instance of processing errors associated with such event.
Proven Expertise in SiC & GaN Materials for RF Applications
With more than 30 years of development and manufacturing experience, Wolfspeed is driving innovation with the industry’s broadest range of SiC and GaN materials. Delivering semi-insulating substrates and nitride epitaxy options up to the newly available diameter of 150mm, Wolfspeed materials enable performance far exceeding that of any other technology, for telecom, aerospace, or defense applications with world-leading bandwidth, efficiency and frequency of operation.
When you partner with Wolfspeed, you get the best and most innovative materials.
High Purity Semi-Insulating (HPSI) SiC Substrates Product Descriptions
4H-SiC, HPSI, Research Grade, 100mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ 32.5mm Flat, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
4H-SiC, HPSI, Production Grade, 100mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ 32.5mm Flat, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
4H-SiC, HPSI, Research Grade, 150mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ Notch, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
4H-SiC, HPSI, Production Grade, 150mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ Notch, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
Wolfspeed’s High Purity Semi-Insulating wafers are not vanadium-doped
Dimensional Properties, Terminology and Measurements
Linear dimension of the flat measured with automated optical micrometer.
The flat of the longest length on the wafer, oriented such that the chord is parallel with a specified low-index crystal plane. Not applicable to 150mm wafers.
Primary Flat Orientation
The primary flat is the (1100) plane with the flat face parallel to the  direction.
A flat of shorter length than the primary flat, whose position with respect to the primary flat identifies the face of the wafer. Not applicable to 150mm wafers.
Secondary Flat Orientation
The secondary flat is 90˚ clockwise from the primary flat, +/-5˚, referencing the silicon face up.
For silicon face polished material, the carbon face of each individual wafer is laser-marked with OCR-compatible font, similar to the definitions and characteristics in SEMI M12. The laser markings are offset right when looking at the carbon face with the primary flat oriented down. For carbon face polish material, the silicon face of each individual wafer is laser-marked.
150 MM HPSI Marking and Notch:
All 150 mm HPSI products have a notch with 1.0 mm (+0.25,-0.00) depth. A line drawn from the wafer center to the notch is parallel to the [1-100] ±5.0 deg direction. The laser markings are offset right when looking at the carbon face with the notch oriented down.