For the first time a vertical-cavity surface-emitting laser (VCSEL) with a single-mode wavelength-tuning over 102 nm in the range of 1550 nm is demonstrated. The fiber-coupled optical output power has a maximum of 3.5 mW and is > 2 mW over the entire tuning range. The sidemode suppression ratios are > 45 dB. The wavelength tuning is achieved with the micro-electro mechanical actuation of a mirror membrane fabricated with surface micro-machining for on-wafer mass production. The mirror membrane consists of low cost dielectric materials (SiOx/SiNy) deposited with low temperature (< 100°C) Plasma Enhanced Chemical Vapor Deposition (PECVD).

The spectroscopic application of a new broadband microelectromechanical-system-tunable vertical cavity surface-emitting laser with single-mode coverage of 60 nm (245 cm(-1)) in a single, continuous sweep is described. The operation of the device is illustrated with high-resolution spectra of CO and CO2 over 110 cm(-1) (27 nm) and 67 cm(-1) (17 nm), respectively, with the CO band shown for high-pressure scans between 1 and 3 bars (0.1-0.3 MPa). The achieved tuning range opens up new opportunities for tunable diode laser absorption spectroscopy. The spectra were compared with HITRAN-derived model calculations. The benefits of a sensor based on this laser are greater speed, laser power, and tuning range.

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This paper presents the investigations of thin dielectric silicon oxide (SiOx) and silicon nitride (SiNx) films deposited below 100 °C by a plasma enhanced chemical vapour deposition (PECVD) using an inductively coupled plasma (ICP)‐source. The influence of the deposition pressure and the applied RF‐power to the plasma from the ICP‐source and a second RF‐power at substrate electrode on the characteristics of the deposited films are studied. The investigated characteristics are refractive index R.I. at 632 nm, deposition rate Rdep, stress σ and etching rate Retch in buffered hydrofluoric acid (BHF). Measurements from electron spectroscopy for chemical analysis (ESCA) support the investigations. The results are discussed and compared with other PECVD deposition methods. A significant influence of the RF‐generator connected to substrate electrode on etching rate and hence on film quality is identified for SiOx but the converse effect is identified for SiNx‐films.