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Silicon-On-Insulator (SOI) technology exhibits significant performance advantages over conventional bulk silicon technology in both electronics and optoelectronics. In this chapter we present an overview of recent applications on light emission from SOI materials. Particularly, in our work we used SOI technology to fabricate light emitting diodes (LEDs), which emit around 1130 nm wavelength with an external quantum efficiency of 1.4 × 10−4 at room temperature (corresponding to an internal quantum efficiency close to 1 %). This is almost two orders of magnitude higher than reported earlier for SOI LEDs. This large improvement is due to three carrier confinement mechanisms: geometrical effects, quantum-size effects, and electric field effects. Our lateral p+/p/n+ structure is powered through two very thin silicon slabs adjacent to the p+/p and n+/p junction. Such use of thin silicon films aims to reduce the p+ and n+ contact area and to confine the injected carriers in the central lowly doped p-region. With this approach, we realized an efficient compact infrared light source with high potential switching speed for on-chip integration applications.

Luminescence properties of silicon light emitting diodes with engineered dislocation loops were investigated. Dislocation loops were formed by Si+-ion implantation above and below metallurgical p+-n junction followed by an annealing step. The diodes showed characteristic dislocation (D-band) and band-to-band luminescence. Measurements of carrier-injection level dependence of the D-band signal intensity were performed. The results are in agreement with the model for dislocation luminescence, which suggests rediative transition between two, dislocation-related shallow levels. A gradual blue-shift of the D-band peak positions was observed with an increase in the carrier injection level in electroluminescence and photoluminescence. A supposition about existence of strong Stark effect for the excitonic dislocation states allows explaining the observations. Namely, in the build-in electric field of the p-n junction the exciton energies are red-shifted. The injected charge carriers lower the field and thus cause the blue-shift of the peak positions. A fitting of the data using the quadratic Stark effect equation suggests 795 meV for the spectral position of D1 peak at 300 K and 0.0186 meV/(kV/cm)2 for the characteristic constant.

The influence of interface recombination on the electroluminescence profile of a lateral p+/p/n+ light emitting diode fabricated on Silicon On Insulator (SOI) materials has been experimentally investigated. Our device resembles a MOSFET fabricated on SOI, except that the source region has opposite doping to the drain. By controlling the voltage bias at the poly gate on top of active emitting region in association with a bias on the silicon substrate under the active region we were able to diminish the non-radiative recombination component at Si/SiO2 interface and therefore enhance the radiative recombination in the thin film SOI. When the diode is working under constant current condition, we observe an increased light output of ~ 20 % as the gate and/or the substrate are biased negatively. The intensity profile across the device is also strongly influenced. To understand the device thoroughly, the structure has also been simulated showing agreement with experimental results.

We measured the electron density and electron energy distribution function (EEDF) of plasmas in our reactor which is intended for silicon oxide and nitride deposition. Langmuir- probe measurements showed that the EEDF of Ar plasma could largely be described by the Maxwell-Boltzmann (MB) distribution function, but it also contained a fraction (~0.5 %) of fast electrons in the energy range between 20 and 40 eV, strongly deviating from the MB distribution. We also measured relative mean electron temperatures (kTe) by optical emission spectroscopy (OES) which were calibrated by the absolute Langmuir-probe measurements. The kTe as measured by OES in Ar plasma decreased from 1.7 eV at 1.1 Pa to 1.4 eV at 12 Pa, while Langmuir-probe measurements showed a decrease from 1.7 eV to 0.8 eV. This difference is caused by the OES method, which is especially sensitive to the fraction of fast electrons in the plasma. OES can be used instead of Langmuir-probe measurements when depositing plasmas are used. Combining both methods, we demonstrated that EEDFs as measured by the Langmuir probe in Ar-N2, and Ar-N2O plasmas, resemble EEDFs in plasmas with small additions of silane, provided that (a) precursor fractions in plasma are small (SiH4 {less than or equal to} 0.8 % and N2O {less than or equal to} 15 %), and (b) total pressure does not exceed 3.6 Pa (27 mTorr). As such, the measured EEDF without silane can be used as input for chemical modeling and optimization of deposition processes in plasmas containing silane.

We measured electron density and electron energy distribution function (EEDF) vertically through our reactor for a range of process conditions and for various gases. The EEDF of Ar plasma could largely be described by the Maxwell-Boltzmann distribution function, but it also contained a fraction (~ 1E- 03) of electrons which were faster (20-40 eV). At low pressures (6.8-11 ubar), the fast-electron tail shifted to higher energies (Emax ~ 50 eV) as we measured more towards the chuck. The fast-electron tail shifted to lower energies (Emax ~ 30 eV) when we increased pressure to 120 ubar or applied an axial magnetic field of 9.5 uT. Addition of small amounts of N2 (1- 10%) or N2O (5%) to Ar plasma lowered the total density of slow electrons (approx. by a factor of two) but did not change the shape of the fast-electron tail of the EEDF. The ionization degree of Ar-plasma increased from 2.5E-04 to 5E-04 when a magnetic field of 9.5 uT was applied.

The influence of interface recombination on the electroluminescence profile of a lateral p+/p/n+ light emitting diode fabricated on Silicon On Insulator (SOI) materials has been experimentally investigated. Our device resembles a MOSFET fabricated on SOI (1), except that the source region has opposite doping to the drain. By controlling the voltage bias at the poly gate on top of active emitting region in association with a bias on the silicon substrate under the active region we were able to diminish the non- radiative recombination component at Si/SiO2 interface and therefore enhance the radiative recombination in the thin film SOI. When the diode is working under constant current condition, we observe an increased light output of ~ 20 % as the gate and/or the substrate are biased negatively. The intensity profile across the device is also strongly influenced. To understand the device thoroughly, the structure has also been simulated showing agreement with experimental results.

In this work, amorphous silicon films with preformed a-Si lines were crystallized using a diode pumped solid state green laser irradiating at 532 nm. The possibility of controllable formation of grain boundaries was investigated. The crystallization processes in the rapidly melted silicon films were discussed. The influence of the crystallization parameters (i.e., energy density, scan velocity, etc.) and structure type (i.e., with and without preformed lines) on properties of the crystallized films was studied. The laser treatment with an energy density of 1.00 J/cm2 at a laser pulse overlapping of 90% provided the optimal crystallization process with predefined grain boundary location. X-ray diffraction (XRD), SEM and AFM microscopy have been used to characterize the crystallized silicon films.

As the semiconductor industry strives toward wafer postprocessing and three-dimensional integration, a demand has arisen for high-quality thin films deposited at temperatures below 400°C. In this work, we present SiO2films deposited at near room temperature, using a multipolar electron cyclotron resonance (ECR) plasma source, introducing the SiH4gas by using a high-velocity jet of silane diluted in helium. The electrical properties were studied under varying deposition parameters, such as gas flow rate, deposition pressure, and postdeposition and postmetallization annealing processes. At a low pressure, low SiH4flow and high helium flow, device-quality SiO2layers were obtained after a deposition combined with a 5minpostmetallization annealing at 400°C. These layers exhibited a refractive index of 1.46, an O∕Siratio of 2, an interface trap density in the order of 1011cm−2eV−1, an oxide charge density down to 1010cm−2, and a breakdown field up to 11MV∕cm. They are thus suitable as a gate dielectric in a thin-film transistor.

The influence of interface recombination on the electroluminescence profile of a lateral p+/p/n+ light emitting diode fabricated on Silicon On Insulator (SOI) materials has been experimentally investigated. Our device resembles a MOSFET fabricated on SOI, except that the source region has opposite doping to the drain. By controlling the voltage bias at the poly gate on top of active emitting region in association with a bias on the silicon substrate under the active region we were able to diminish the non-radiative recombination component at Si/SiO2 interface and therefore enhance the radiative recombination in the thin film SOI. When the diode is working under constant current condition, we observe an increased light output of ~ 20 % as the gate and/or the substrate are biased negatively. The intensity profile across the device is also strongly influenced. To understand the device thoroughly, the structure has also been simulated showing agreement with experimental results.

We measured the electron density and electron energy distribution function (EEDF) of plasmas in our reactor which is intended for silicon oxide and nitride deposition. Langmuir- probe measurements showed that the EEDF of Ar plasma could largely be described by the Maxwell-Boltzmann (MB) distribution function, but it also contained a fraction (~0.5 %) of fast electrons in the energy range between 20 and 40 eV, strongly deviating from the MB distribution. We also measured relative mean electron temperatures (kTe) by optical emission spectroscopy (OES) which were calibrated by the absolute Langmuir-probe measurements. The kTe as measured by OES in Ar plasma decreased from 1.7 eV at 1.1 Pa to 1.4 eV at 12 Pa, while Langmuir-probe measurements showed a decrease from 1.7 eV to 0.8 eV. This difference is caused by the OES method, which is especially sensitive to the fraction of fast electrons in the plasma. OES can be used instead of Langmuir-probe measurements when depositing plasmas are used. Combining both methods, we demonstrated that EEDFs as measured by the Langmuir probe in Ar-N2, and Ar-N2O plasmas, resemble EEDFs in plasmas with small additions of silane, provided that (a) precursor fractions in plasma are small (SiH4 {less than or equal to} 0.8 % and N2O {less than or equal to} 15 %), and (b) total pressure does not exceed 3.6 Pa (27 mTorr). As such, the measured EEDF without silane can be used as input for chemical modeling and optimization of deposition processes in plasmas containing silane.

We measured electron density and electron energy distribution function (EEDF) vertically through our reactor for a range of process conditions and for various gases. The EEDF of Ar plasma could largely be described by the Maxwell-Boltzmann distribution function, but it also contained a fraction (~ 1E- 03) of electrons which were faster (20-40 eV). At low pressures (6.8-11 μbar), the fast-electron tail shifted to higher energies (Emax ~ 50 eV) as we measured more towards the chuck. The fast-electron tail shifted to lower energies (Emax ~ 30 eV) when we increased pressure to 120 μbar or applied an axial magnetic field of 9.5 μT. Addition of small amounts of N2 (1- 10%) or N2O (5%) to Ar plasma lowered the total density of slow electrons (approx. by a factor of two) but did not change the shape of the fast-electron tail of the EEDF. The ionization degree of Ar-plasma increased from 2.5E-04 to 5E-04 when a magnetic field of 9.5 μT was applied.

The influence of interface recombination on the electroluminescence profile of a lateral p+/p/n+ light emitting diode fabricated on Silicon On Insulator (SOI) materials has been experimentally investigated. Our device resembles a MOSFET fabricated on SOI (1), except that the source region has opposite doping to the drain. By controlling the voltage bias at the poly gate on top of active emitting region in association with a bias on the silicon substrate under the active region we were able to diminish the non- radiative recombination component at Si/SiO2 interface and therefore enhance the radiative recombination in the thin film SOI. When the diode is working under constant current condition, we observe an increased light output of ~ 20 % as the gate and/or the substrate are biased negatively. The intensity profile across the device is also strongly influenced. To understand the device thoroughly, the structure has also been simulated showing agreement with experimental results.

In this work, amorphous silicon films with preformed a-Si lines were crystallized using a diode pumped solid state green laser irradiating at 532 nm. The possibility of controllable formation of grain boundaries was investigated. The crystallization processes in the rapidly melted silicon films were discussed. The influence of the crystallization parameters (i.e., energy density, scan velocity, etc.) and structure type (i.e., with and without preformed lines) on properties of the crystallized films was studied. The laser treatment with an energy density of 1.00 J/cm2 at a laser pulse overlapping of 90% provided the optimal crystallization process with predefined grain boundary location. X-ray diffraction (XRD), SEM and AFM microscopy have been used to characterize the crystallized silicon films.