A study into the formation and characterisation of electroless nickel silicide for laser doped solar cells
In this paper we will study the formation and characteristics of nickel silicide compounds and the subsequent specific contact resistivity (Ω.cm2) during the formation of an ohmic contact in solar cells. Using Transmission Line Method (TLM) we will analyse the electrical characteristics of the formed nickel silicides at different sintering temperatures and durations. In each sintering condition tested, the relationship between the total resistance and the distance between the contact pads on the fabricated test structures is measured and graphed. From these graphs the contact resistance (Ω) and specific contact resistivity (Ω.cm2) of the metallisation stack is calculated and tabulated. We conclude the paper by showing the optimum sintering condition of 350°C for three minutes for laser doped solar cells which yields negligible contact resistance.
Investigation on the barrier height and inhomogeneity of nickel silicide Schottky
Abstract The apparent Schottky barrier height (SBH) of the nickel silicide Schottky contacts annealed at different temperatures was investigated based on temperature dependence of I – V characteristic. Thermionic emission–diffusion (TED) theory, single Gaussian and double Gaussian models were employed to fit I – V experimental data. It is found the single Gaussian and double Gaussian SB distribution model can give a very good fit to the I – V characteristic of apparent SBH for different annealing temperatures. Also, the apparent SBH and the leakage current increase with annealing temperatures under reverse voltage. In addition, the homogeneity of interfaces for the samples annealed at temperatures of 500 and 600 °C is much better than that of the samples annealed at temperatures of 400, 700, and 800 °C. This may result from the phase transformation of nickel silicide due to the different annealing temperatures and from the low Schottky barrier (SB) patches.
A revision of the genus Rhinotorus Förster, 1869 (Hymenoptera, Ichneumonidae, Ctenopelmatinae), with descriptions of three new species and an illustrated identification key
The genus Rhinotorus Forster, 1869 is revised. Thirteen species are recognized including 3 species that are new to science ( R. jussilai sp. nov., R. campester sp. nov., R. tarsilatus sp. nov.). Saotis brachycerus (Kasparyan & Kopelke, 2009) comb. nov. is considered to be a member of the genus Saotis . Rhinotorus similis (Brischke, 1892) is tentatively recorded from Austria and Sweden for the first time. A number of new host records are also provided: Cladius pectinicornis (Geoffroy, 1785) for R. leucostomus (Gravenhorst, 1829), Nematus lucidus (Panzer, 1801) for R. nasutus (Gravenhorst, 1829) and N. papillosus (Retzius, 1783) for R. jussilai sp. nov.