RFSi wafers

RFSi wafer family in 150-200mm – High Resistivity for RF application needs

Okmetic’s High Resistivity silicon wafers aimed at the RF market are optimal for all types of Acoustic Wave Filters, IPD devices, Power Amplifiers, Integrated RFIC & PA and Silicon Interposers. By using Okmetic’s superior High Resistivity silicon wafers as substrates, you can improve the electrical performance of your RF applications. The cutting-edge wafer technology reduces RF losses and provides stable “effective resistivity” over frequency range, resulting in higher Q values. The technology also helps improve linearity, minimize  intermodulation and second harmonics distortion, and reduce characteristic stress and bow. Okmetic’s Advanced MCz (Magnetic Czochralski) crystal growth recipes can customize oxygen content to increase resistivity and conductivity type stability, while still maintaining structural integrity.

Okmetic provides the market’s widest range of wafer thicknesses ranging from 200 to 1500 μm. Customers find the thinner options very attractive in packaging designs whereas in mixed metal lattices like GaN epi layers, the customers enjoy the benefits of the thicker substrates to offset the extreme stresses. Okmetic can customize the Resistivity, Crystal Orientation, Oxygen, and Thickness to your product or package needs.

RFSi wafers improve RF device performance and TCO and enable more ambitious device designs

  • Superior performance in 2nd harmonics, Insertion losses, Intermodular Distortion and Q-values. 
  • Engineered High Resistivity wafers replacing many earlier FZ based products.
  • Okmetic’s variety of wafer thickness and backside film options help stress management of GaN-on-Si RF Power substrates.
  • In-house process from crystal pulling and wafering to patterning and SOI gives Okmetic ability to combine technologies and offer Customers new types of value-added wafers by e.g. combining
  • C-SOI® structure with low-loss device layer material as a base for a new BAW resonator. 

High Resistivity and Engineered High Resistivity wafer spec chart

RF Gan wafers for GaN On Si applications tailored on customer needs

  • Available in 150 and 200 mm wafer sizes
  • Tailored to match the demanding GaN epi needs
  • High Resistivity: P-, up to ≥ 7000 Ohm-cm resistivity with suitable Oi control, balancing in between the resistivity stability and lattice integrity.
  • On-orientation <111> with tight orientation control. Competing High Resistivity FZ material is very hard to make in <111>.
  • Custom wafer thickness options for reducing wafer bow and warpage (150mm up to 1300µm, 200mm up to 1500µm).
  • Poly and LTO options for the back surface for further stress management
  • Also Double Side Polished wafer available, if needed.
  • SOI based wafer for advanced GaN-on-Si structures

High Resistivity BSOI wafer with suspended low-loss structures meeting the mm wave device needs

Frequencies beyond acoustics in the mm wave bands

• Lumped element solutions combined with novel approaches such as strip line filters are a promising new technology


•Combining the high resistivity substrate features in a turn key cavity SOI structure
•Simplified structures for integrated sensors & communications chips – available also for strip line platforms