Forschungsnews

A recently installed DRIE tool enables flexible through silicon substrate etching, needed to form, e.g., through silicon vias used to integrate InP-based devices with silicon and to fabricate micro gas cells.

In a joint project with PTB, we are developing a compact atomic magnetometer, which uses frequency-stabilized lasers and vaporized cesium atoms.

Scientists at FBH investigated the wavelength tuning behavior in high-power distributed feedback (DFB) lasers. The results reveal insight to the mechanisms leading to mode hops in those lasers and the conditions for devices with a large continuous wavelength tuning range.

FBH develops low-noise and broadband transimpedance amplifiers for communications and sensing applications using InP HBT devices.

FBH and MBI scientists spatially mapped the light emission from the active region of aged LEDs under electrical and optical excitation. This provided insights into the degradation mechanisms and the role of the distribution of current and radiative recombination.

By implementing optimizations to our Al-core PCB design, reducing the thermal resistance, FBH has observed an increase of up to 20% in the emission power of far-UVC-LEDs.

We have developed a novel dual and convergent arrangement of ICP sources in cooperation with Ruhr University Bochum and tested it to deposit primarily SiO₂. Due to the versatile setup possibilities, it can be efficiently used for different coating processes.

FBH researchers developed an effective technique to manipulate temperature distribution within broad emitters. It has been shown that a well-defined emitter sub-structure can flatten the adverse thermal lens and produce narrower beam divergence and higher efficiency.

A novel Bragg grating-based frequency reference module complements our latest generation of laser modules. It facilitates accurate frequency control. Autonomous operation of the combined laser system is enabled by a smart industry-grade control platform.

Improved material quality of aluminum gallium nitride (AlGaN) was achieved by high-temperature annealing using a sapphire (Al₂O₃) cover to protect the surface. Oxygen helps to maintain optical transparency while decreasing the defect density.

The FBH has developed a red-emitting DBR tapered laser at a wavelength of 660 nm. With an almost single-mode emission and more than 1 W optical output power, this laser is suitable to generate entangled photons for quantum-OCT.

FBH has realized the first GaN-based digital class-E outphasing power amplifier module for 5G applications. The design concept is an important step to push efficiency of 5G base stations and to advance digitization for next-generation communication.

We have successfully fabricated a novel type of suspended photonic crystal cavities in diamond by implementing a quasi-isotropic dry etching process in O₂-plasma. These devices are key components for next-generation quantum communication technologies.

Recently, FBH started operating a new sputter tool based on the principle of a quasi-vertical deposition process. The tool concept ensures a cross-contamination free process and is used to deposit e.g. iridium as a Schottky barrier metal.

FBH scientists have developed a monolithic double quantum well laser featuring a tapered gain section for ultrashort pulse generation. The generated picosecond pulses with high peak power can be further compressed and utilized for THz-pulse generation.

SERDS using 785 nm dual-wavelength diode lasers is a powerful technique for soil inspection under the influence of strong fluorescence interference. This could help to improve crop productivity as well as soil health and to reduce fertilizer usage.

We have realized a compact power amplifier using our InP MMIC process, achieving a maximum output power of 12.5 dBm with 17% efficiency. The circuit is equipped with low-temperature indium bumps for flip-chip mounting.

FBH recently installed a Helios 5 UX dual beam system that combines a focused gallium ion beam with a scanning electron microscope. The instrument will be used for microscopic analysis of materials and devices as well as for rapid prototyping of nano-optical components.