MODELING OF TUNELLING CURRENT IN ANISOTROPIC Si/Si1-x Gex/Si HETEROJUNCTION BIPOLAR TRANSISTOR AND ITS VERIFICATION

• Main Author: HASANAH (NIM 30203005), LILIK
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/10805
• Institution: Institut Teknologi Bandung

Recently, electronic device grows very fast along device performance going to better direction. This device performance improvement is caused by the possibility to arrange greater number of transistor in a chip of integrated circuit and the transistor size is get smaller. Until now, silicon is the cheapest microelectronic technology for integrated circuit so it's dominating the electronic device industry. There are disadvantages of silicon such as mobility and low saturation speed that gives opportunity to other semiconductor material to be used in microelectronic integrated circuit.<p> SiGe technology ability to arrange band gap and strain in silicon layer is hoped to overcome the silicon's disadvantages but retain advance and cheap fabrication process. At present time, Si/Si1-xGex/Si heterojunction bipolar transistor makes possible the ability to get higher gain, high speed performance, and relative suitability with currently available silicon technology.<p> Theoretical study is useful to study and predict the new Si/Si1-xGex/Si heterojunction bipolar transistor characters. Several carrier transport model such as drift-diffusion, energy-transport, hydrodynamic-transport, and quantum-transport can be used to model device heterostructure. With the size of the device gets smaller and smaller, quantum effect becomes more real and have to be included in the current calculation.<p>Electron transmittance calculation can be done in two ways, which are analytically and transfer matrix method. Analytical description of the electron transmittance through the anisotropic Si(110)/Si1-xGex/Si(110) heterostructure is done by solving the Schrdinger equation that including off-diagonal effective-mass tensor elements. Analytical transmittance calculation is tested with numeric transmittance calculation using transfer matrix method. From this calculation, both methods present the same result. <br />