Harjana Harjana
Jurusan Fisika FMIPA Universitas Sebelas Maret (UNS)

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Electrical Characteristics and Annealing Effect on Al/n-GaSb Schottky Diode Doped Using DMTe Ari Handono Ramelan; Harjana Harjana; Pepen Arifin; Ewa Goldys
Jurnal Matematika & Sains Vol 15, No 3 (2010)
Publisher : Institut Teknologi Bandung

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The electrical properties of Al/n-GaSb Schottky diodes, doped with 1.4 × 1018 cm−3 (tellurium) were examined.  C-V (capacitance-voltage) measurements at 300 K show barrier heights of 0.63 eV, compared to 0.59 eV determined from room temperature I-V (current-voltage)  measurements. The voltage and frequency dependence on the capacitance is due to the ideality factor of the Schottky barrier and due to a high series resistance.  At low frequency the measured capacitance is dominated by the depletion capacitance of the Al/n-GaSb Schottky diode which is bias-dependent and frequency-dependent. The diode shows a strong temperature dependence of ideality factor from approximately 3.6 at room temperature to as high as 6.7 at 140 K.  There may be a small portion of the device nonideality attributable to generation-recombination currents due to deep levels in GaSb. The barrier height decreased from 0.57 eV to 0.35 eV for the sample annealed at 300oC for 1 minute.
Drought Risk Reduction Efforts in The Village of Krendowahono Gondangrejo Karanganyar Using Geolistric Surveys Sorja Koesuma; Budi Legowo; Darsono Darsono; Iwan Yahya; Harjana Harjana
Social, Humanities, and Educational Studies (SHEs): Conference Series Vol 3, No 1 (2020): Social, Humanities, and Educational Studies (SHEs): Conference Series
Publisher : Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/shes.v3i1.45014


Krendowahono, Gondangrejo, Karanganyar regency is located in the north of Surakarta city which is in 2019 the most affected area of drought. During August 2019 to November 2019, the village needs 2 to 5 water tanks dropping per day with a capacity of 5000 liters per tank. With such drought conditions, the villages government should provide clean water for their citizens. The method used for determining groundwater aquifers is the Geoelectric Method. This method works by injecting an electric current into the ground surface, then measuring the potential difference. Based on the obtained resistivity value, it can be interpreted at what depth there are groundwater aquifers. At the geoelectric survey location in Krendowahono village, it was found that the groundwater aquifer might be in layer 5 at a depth of 92.3 meters below, but the groundwater potential at this layer was not huge enough. Potential aquifers are likely to be from a depth of 92.3 meters to 110-120 meters.