The principal ideas of the thin-disk laser design will be illustrated and the advantages for operating different laser materials will be explained. The results for continuous-wave (CW) and Q-switched operation as well as for amplification of short (nanosecond) and ultrashort (picosecond, femtosecond) pulses demonstrate the potential of the thin-disk laser design. The scaling laws for this laser design show that the power limit for CW operation is far beyond 40 kW for one single disk and the energy limit is higher than 3 J from one disk in pulsed operation. Also, the applicability of the thin-disk laser concept to optically pumped semiconductor structures will be discussed. When pumping directly into the quantum wells, the energy defect between the pump photon and the laser photon can be smaller than 5%, thus reducing the waste heat generated inside the semiconductor structure. First results demonstrate the potential of this new concept. Finally, a short overview of the industrial realization of the thin-disk laser technology will be given.

Fifteen Years of Work on Thin-Disk Lasers: Results and Scaling Laws

By doping an organic compound functioning as an electron donor (hereinafter referred to as donor molecules) into an organic compound layer contacting a cathode, donor levels can be formed between respective LUMO (lowest unoccupied molecular orbital) levels between the cathode and the organic compound layer, and therefore electrons can be injected from the cathode, and transmission of the injected electrons can be performed with good efficiency. Further, there are no problems such as excessive energy loss, deterioration of the organic compound layer itself, and the like accompanying electron movement, and therefore an increase in the electron injecting characteristics and a decrease in the driver voltage can both be achieved without depending on the work function of the cathode material.

Light Emitting Device

Recent developments in semiconductor disk lasers (SDLs) generating visible or ultraviolet light are reviewed. After an introduction on potential applications, we discuss how the combination of vertical-emitting semiconductor GaAs-based structures and intra-cavity nonlinear conversion techniques can be successfully exploited to uniquely meet demands for continuous-wave radiation in the visible and ultraviolet spectral range. To do so, an overview of the device operating princi- ples and performance is presented highlighting the underlying material considerations, semiconductor structural designs, thermal management techniques and suitable cavity configurations. This summary is completed by a presentation of new developments in the field, with a particular focus on the trends towards miniaturization.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/lpor.200810042

Semiconductor disk lasers for the generation of visible and ultraviolet radiation

A method of fabricating a surface emitting semiconductor laser includes a first step of forming, on a substrate, multiple monitor-use semiconductor layers having stripes radiating from a center of the substrate, and a laser portion that includes semiconductor layers and is located on the periphery of the multiple monitor-use semiconductor layers, a second step of monitoring oxidized conditions on the multiple monitor-use semiconductor layers when a selectively oxidized region is formed in the laser portion, and a third step of controlling oxidization of the selectively oxidized region on the basis of the oxidized conditions thus monitored.

Surface emitting semiconductor laser

In one embodiment, semiconductor die are singulated from a semiconductor wafer by etching openings completely through the semiconductor wafer.

Semiconductor die singulation method

The invention is directed to an optically pumped surface-emitting semiconductor laser device having at least one radiation-generating quantum well structure and at least one pump radiation source for optically pumping the quantum well structure, whereby the pump radiation source comprises an edge-emitting semiconductor structure. The radiation-generating quantum well structure and the edge-emitting semiconductor structure are epitaxially grown on a common substrate. A very efficient and uniform optical pumping of the radiation-generating quantum well structure is advantageously possible with this monolithically produced semiconductor laser device. Methods for manufacturing inventive semiconductor laser devices are also specified.

Optically pumped, surface-emitting semiconductor laser device and method for the manufacture thereof

A light-emitting semiconductor component which contains a sequence of semiconductor layers ( 2 ) with an area of p-doped semiconductor layers ( 4 ) and n-doped semiconductor layers ( 3 ) between which a first pn junction ( 5 a, 5 b ) is formed. The pn junction ( 5 a, 5 b ) is subdivided into a light-emitting section ( 7 ) and a protective-diode section ( 8 ) in a lateral direction by means of an insulating section ( 6 ). An n-doped layer ( 9 ), which forms a second pn junction ( 10 ) which acts as a protective diode along with the p-doped area ( 4 ), is applied to the p-doped area ( 4 ) in the area of the protective-diode section ( 8 ), the first pn junction ( 5 b ) in the protective-diode section ( 8 ) having a larger area than the first pn junction ( 5 a ) in the light-emitting section ( 7 ). The protective-diode section ( 8 ) protects the light-emitting semiconductor component from voltage pulses due to electrostatic discharges (ESD).

Light-Emitting Semiconductor Component Comprising a Protective Diode

A method for production of a plurality of semiconductor chips (6) in a wafer composite. A semiconductor layer sequence (2) is grown on a growth substrate (1), metallization (3) is applied to the semiconductor layer sequence (2), a metal layer (4) is electrochemically deposited onto the metallization (3), and the semiconductor layer sequence (2) is then structured and separated to form individual semiconductor chips (6). The electrochemically applied metal layer (4) is particularly suitable for use as a heat spreader, for dissipation of the heat produced by the semiconductor chips (6).

Method for production of a plurality of semiconductor chips, and a semiconductor component

The use of oxide confined VCSELs in datacom applications is demonstrated. The devices exhibit low threshold currents of approximately 3 mA and low electrical series resistance of about 50 (Omega) . The emission wavelength is in the 850 nm range. Life times of the devices are several million hours under normal operating conditions. VCSEL arrays are employed in a high performance parallel optical link called PAROLITM. This optical ink provides 12 parallel channels with a total bandwidth exceeding 12 Gbit/s. The VCSELs optimized for the parallel optical link show excellent threshold current uniformity between channels of < 50 (mu) A. The array life time drops compared to a single device, but is still larger than 1 million hours.

VCSELs for datacom applications

Die Erfindung bezieht sich auf eine optisch gepumpte oberflachenemittierende Halbleiterlaservorrichtung mit mindestens einer strahlungserzeugenden Quantentopfstruktur (11) und mindestens einer Pumpstrahlungsquelle (20) zum optischen Pumpen der Quantentopfstruktur (11), bei der die Pumpstrahlungsquelle (20) eine kantenemittierende Halbleiterstruktur (21) aufweist. Die strahlungserzeugende Quantentopfstruktur (11) und die kantenemittierende Halbleiterstruktur (21) sind auf einem gemeinsamen Substrat (1) epitaktisch aufgewachsen. Mit dieser monolithisch hergestellten Halbleiterlaservorrichtung ist vorteilhafterweise ein sehr effektives und homogenes optisches Pumpen der strahlungserzeugenden Quantentopfstruktur moglich. Weiterhin sind Verfahren zum Herstellen von erfindungsgemasen Halbleiterlaservorrichtungen angegeben.

Tony Albrecht

Papers

Optically pumped, surface-emitting semiconductor laser device and method for the manufacture thereof

Light-Emitting Semiconductor Component Comprising a Protective Diode

Method for production of a plurality of semiconductor chips, and a semiconductor component

VCSELs for datacom applications

Optisch gepumpte oberflächenemittierende Halbleiterlaservorrichtung und Verfahren zu deren Herstellung