Type 4DSFx diodes are fabricated by ACST Film-Diode (FD) Process and are designed for applications at frequencies up to W-Band (75-110GHz). FD-Structures are implemented on a transferred membrane-Substrate, which is just few µm thin and of a low dielectric constant insulator. This allows for a drastic reduction of structure parasitic and, therefore, aims at ultimate performance at high frequencies. Optically-transparent membrane-substrate allows for accurate positioning for diode mounting/assembly.
The 4DSFx structure represents a single-anode Schottky diode, optimised for operation in Varistor mode under Zero-Bias Condition. Low differential resistance enables easy matching with 50 Ohm reading electronics, which is of a crucial importance for high-speed electronics (i.e. high bit-rate data transmission systems).
Beside traditional approaches for mounting MM-Wave diodes by soldering and gluing with conductive epoxies, the 4DSF20 diodes are also suitable for mounting by thermo-compression in a similar manner as beam-lead diodes. Main advantages of thermo-compression diode mounting approach is that it does not require any hazardous material like is flux or soldering paste, and is suitable for automatic process using automatic pick-up and precision positioning machines. This option offers major advantages in comparison to soldering and gluing approaches in terms of reliability and assembly costs.