東南大學(xué)電子器件-金半接觸(文件)
【正文】 emiconductor contact, having a linear IV characteristic in both biasing directions. For example, the interconnected lines (互連線 )are required in IC. So, it is important that such contacts be ohmic, with minimal resistance and no tendency to rectify signals. R The barrier to electron flow between the metal and semiconductor is small and easily overe by a small voltage. Case 1 M/n type, qΦmq Φs Case 2: metalp type semiconductor, q?m q?s Unlike the rectifying contacts, no depletion region occurs in the semiconductor in these two cases since the electrostatic potential difference required to align the Fermi level at equilibrium calls for accumulation of majority carriers in the semiconductor. Ohmic contacts(practical) In practice, it is always impossible for us to form the ohmic contacts of metalsemiconductor by choosing the appropriate work function of the metal. The reason is that the semiconductor surface contains surface states due to inplete covalent bonds. The metal/semiconductor contacts form always a barrier whatever metals are used. So, to obtain the ohmic contacts for metal/semiconductor, a practical method is by doping the semiconductor heavily in the contact regions. Therefore, if a barrier exists at the interface, the depletion width is small enough to allow carriers to tunnel through the barrier. Tunneling probability can be referred to semiconductor physics(P236238). Typical Schottky Barriers Pinning effect (釘扎效應(yīng)） : because of surface states and interfacial layer – P168 It is easier to obtain the width of the depletion region at MS Schottky junction. 2100021002100)11(2))
語(yǔ)文相關(guān)推薦
鄂ICP備17016276號(hào)-1