Heterojunction Diodes Comprising Nitrogen-Doped Ultrananocrystalline Diamond/Hydrogentad Amorphous Carbon and p-Type Silicon
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2016-09-01 |
| Journal | ECS Meeting Abstracts |
| Authors | Abdelrahman Zkria, Tsuyoshi Yoshitake |
| Institutions | Aswan University |
Abstract
Section titled āAbstractāUltrananocrystalline diamond/hydrogenated amorphous carbon composite (UNCD/a-C:H) films, wherein diamond crystallites with diameters of less than 10 nm are embedded in an a-C:H matrix, have a large absorption coefficients of 10 5 - 10 6 cm -1 in the photon energy range between 3 and 6 eV that make them applicable to optoelectronics devices. Moreover, the realizations of p-type and n-type diamonds are desirable for the applications of diamond-based electronic devices. In this work, the heterojunction diodes comprising nitrogen-doped UNCD/a-C:H and p-type Si were fabricated by coaxial arc plasma deposition (CAPD) and the heterojunction parameters were evaluated from the current-voltage ( IV ) and capacitance-voltage ( CV ) measurements carried out in dark at room temperature. Furthermore, the photodetection performance was studied. Experimentally, n-type UNCD/a-C:H films were deposited on p-type silicon substrate at a substrate temperature of 550 ĀŗC with ambient pressure of 53.3 Pa. the Pd electrode is deposited on both sides by using of Radio Frequency (RF) sputtering. The (I-V) characteristics of the diodes measured in the dark . I-V curve exhibited a rectiļ¬cation ratio of more than 10 4 , which evidently confirms that nitrogen-doped UNCD/a-C:H possesses n-type conduction and easily forms junction with p-type semiconductor. C-V measurements of the diode confirm junction formation, in which capacitance non-linearly decreases with increasing reverse bias voltage. The built-in potential of the heterojunction was estimated to be 0.68 eV from the extended linear part of 1/C 2 plot. From the slop of 1/C 2 , carrier concentration of the UNCD/a-C:H film was estimated to be 6Ć10 15 cm -3 . Here, carrier concentration of Si substrate was 1Ć10 15 cm -3 for the ļ¬tting analysis. The value of depletion region width š UNCD in the UNCD/a-C:H ļ¬lm was estimated to be 200 nm at the reverse voltages of Ā±1 V, which is close to that value generally measured for heterojunctions with closed ranges of carrier concentrations. More details will be explained in presentation during the conference.