Microwave Properties Of Solid State Plasma In Lateral PiN Diode

In a certain condition, the solid state plasma is similar to metal. It is an effective way to achieve the miniaturization of antennas and improve the performance of communication system by the solid state plasma reconfigurable antenna, which is constructed by transverse SPiN diode, compatible with microelectronic technology and able to obtain reconstruction of frequency and direction, becoming a hot research topic at home and abroad.In this paper, focusing on applications of solid state plasma reconfigurable antenna, the working mode, the carrier transport mechanism and the generation mechanism of solid state plasma in SPiN diode are analyzed, a model of solid state plasma's parameter is established by means of effective mass and the characteristics of electromagnetic wave propagation in solid state plasma are described. Plasma frequency is the intrinsic property of solid state plasma, and the lower limit of solid state plasma concentration is 1016cm-3.When the concentration reach 1018cm-3, the solid state plasma is similar to metal, which can be used to make solid state plasma antenna. The variation of dielectric coefficient,refractive index, reflection coefficient and some other key physical parameter with solid state plasma's concentration and frequency of electromagnetic wave is established. The simulation results show that the real part of the dielectric constant change very little with the frequency of electromagnetic wave. It keeps stable with the beginning increase of the concentration of the solid state plasma, and when the concentration reaches 1018cm-3, the real part of the dielectric constant fall down rapidly. The imaginary part decrease with the rise of the electromagnetic wave frequency, and increase with the increasing concentration of solid plasma. The real part of the refractive index increase with the rising concentration,and decreases with the increasing electromagnetic wave frequency. The trend of the imaginary part is same as the real part. The reflection coefficient decreases with the increasing electromagnetic wave frequency and increases with the rising concentration of solid plasma. Skin depth decreases with the increase of the frequency of the incident wave and the concentration of the solid state plasma. According to the actual situation,considering the influence of bipolar diffusion and scattering between carriers and other non-ideal effects on collision frequency of the solid state plasma, the variation model of the key physical parameters of solid state plasma with the electromagnetic wave frequency and solid state plasma concentration is corrected. Under non-ideal effect, the simulation results show that the variation trend of the parameters is basically the same, the dielectric constant,refractive index and reflection coefficient are decreased, the dielectric constant decreases by about 2-3 orders of magnitude, the refractive index fall down by about 1 orders of magnitude, the reflection coefficient is decreased very little, and the skin depth is slightly increased.Based on the above research, the solid state plasma SPiN diode is designed and the process is optimized. The simulation results show that the antenna frequency can be switched with19.9GHz, 14 GHz and 11.7GHz and the goal of reconfiguration is achieved. Now the antenna has been prepared, being tested.