Xiuying Jiang

Structural and optical properties of ZnO film by plasma-assisted MOCVD

High quality ZnO film was deposited by plasma-assisted metal-organic chemical vapor deposition (MOCVD). We observed a dominant peak at 34.6° due to (0 0 2) ZnO, which indicated that the growth of ZnO film was strongly C-oriented. The full-width at half-maximum (FWHM) of the ω-rocking curve was 0.56° indicating relatively small mosaicity. Photoluminescence (PL) measurement was performed at both room temperature and low temperature. Ultraviolet (UV) emission at 3.30 eV was found with high intensity at room temperature while the deep level transition was weakly observed at 2.513 eV. The ratio of the intensity of UV emission to that of deep level emission was as high as 193, which implied high quality of ZnO film. From PL spectrum at 10 K, we observed A-exciton emission at 3.377 eV and D°X bound exciton transition at 3.370 eV. The donor–acceptor transition and LO phonon replicas were observed at 3.333 and 3.241 eV respectively. Raman scattering was performed in back scattering at room temperature. The E2, A1(LO) and A1(TO) mode was seen at 437.6, 575.8 and 380 cm−1 respectively. In comparison with Raman spectrum of ZnO powder, we found that ZnO film was nearly free of strain, which indicated high crystal quality.

The monolithic integration of a superluminescent diode with a power amplifier

Monolithic integration of a superluminescent diode with a tapered semiconductor power amplifier is proposed. The basic operation of the integrated optical source is demonstrated under pulse conditions. Output power obtained by the integrated device is one to two orders of magnitude higher than the conventional superluminescent diode (SLD) devices.

High efficiency top surface‐emitting lasers fabricated by four implantation using tungsten wire as mask

We report the results of a high efficiency room temperature continuous wave (cw) vertical‐cavity surface‐emitting laser. The structure is obtained by four deep H+ implantation using tungsten wires as the mask. The fabrication process is the simplest ever reported in vertical‐cavity surface‐emitting laser fabrication. The largest differential quantum efficiency of 65% and maximum cw light output power over 4 mW have been achieved for the 15×15 μm2 device.

Vertical-cavity surface-emitting laser fabricated by two implantations using tungsten wires as mask

The design and fabrication of a room-temperature continuous wave (cw) vertical-cavity surface-emitting laser is reported. The device was fabricated by two deep H+ implantations using parallel tungsten wires as the resist mask. The direction of the mask in the first implantation is perpendicular to that in the second. The fabrication process is the simplest ever reported for vertical-cavity surface-emitting laser fabrication. A lowest threshold current of 17 mA and a maximum light output power of 4 mW were obtained.

Optical properties of ZnO film by plasma-assisted MOCVD

In this article, non-doped and nitrogen doped ZnO films were deposited by plasma-assisted MOCVD on sapphire substrates. The optical properties were investigated by the measurement of photoluminescence, Raman scattering and ultraviolet absorption. It was found that the N-doped ZnO film displayed better crystal quality and optical characteristics, and, furthermore, the resistivity of doped films was much higher than that of undoped samples.

Influence of annealing on optical properties of ZnO film

No annealed, annealed after growth and annealed during growth ZnO films (denoted s1,s2, and s3 respectively) were grown on C-plane sapphire substrate by plasma-enhanced MOCVD and characterized by XRD and the optical transmission spectra. We could find that there is tensile strain in the c-plane of the films. Furthermore, the tensile strain increases after annealing. At the same time, the optical transmission indicates that the transmission of s2 in visible region is the highest and the value of s3 is the lowest.

Comparison of two kinds of AlGaAs terraced substrate inner stripe superluminescent diodes

We report on two kinds of AlGaAs terraced substrate inner stripe superluminescent diodes: those with SiOx antireflection coatings, and those with unpumped absorbing regions. The devices were fabricated by one-step liquid phase epitaxy. Both kinds of devices suppress stimulating oscillation effectively. The characteristics of the diodes with antireflection coatings are better than those with unpumped absorbing regions. The spectral width of the diodes with antireflection coatings is over 23 nm, the output power is about 7 mW, the modulation depth is less than 5%, and the horizontal divergence angle is smaller than 10–15°.