This paper investigates the capacitance–voltage (C–V) characteristics of F doping SiCOH low dielectric constant films metal–insulator–semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasiloxane (DMCPS) and trifluromethane (CHF3) electron cyclotron resonance plasmas. With the CHF3/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of C–V curves and the increase of flat-band voltage VFB from −6.1 V to 32.2 V are obtained. The excursion of C–V curves and the shift of VFB are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF3/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small VFB of 2.0 V.
This paper presents a method for conformal of a two-connected region k i onto an annulus.The philosophy of the method is to convert the p ~oblem into a Dirichlet problem and to prove the real part of the analytic" function transformation should ~ a harmonic function satisfbing certain boundary conditions. According tc the theo,-'y of hazmonic function we can determine t)e inner radius of the annulus from the condition that the harmonic function uefined in two-connected region should be slngle-valued. It is then easy to see that the, imaginary palt can directly be obtained with the aid of Cauchy-Riemann conditions.The. unknown constants of integration only influence the argumen~ of fmag(~ poii.ts and can easily be derived bq using the one-to-one mapping of ~ region onto an annulus. Without loss of general:ty, t:'~. method can be used to conformally map other two-connected regions onto an annulus if they can be subdivided into sevoral zeccangulars.The method has been programmed for a digital computer. It is demonstrated that the method is efficient and economical. The corresponding numerical results are shown in the Table. ?