Problem 1 (50 Points) Silicon Diffusion Hypothetically, assume a donor constant/infinite diffusion is used to obtain a linear donor doping profile given by n(x) = [(8.0 x 1019) - (1.5 x 1023)x] cm as illustrated in the graph. Note that the doping profile is NOT to scale! The oppositely doped substrate acceptor concentration is given by N= 1 x 1017cm-3. n(x) T8.0 x 1019 cm-3 Doping Profile Na=1 x 1017cm 3 (a) (10 Points) Compute a value for the junction depth, xj, in um. (b) (15 Points) Compute the dose, Q. in atoms-cm2. Note that strictly speaking, you should be evaluating an integral, however, the assumed linear doping profile allows you to significantly simplify this mathematical effort. Think triangles! (c) (15 Points) This constant/infinite diffusion is now capped with an SiO2 layer and we proceed with a finite (limited) source diffusion at a temperature T, for a time t. During this time used for this finite source diffusion, the surface concentration will (INCREASE, DECREASE, REMAIN THE SAME); the junction depth, Xj, will (INCREASE, DECREASE, REMAIN THE SAME); and the dose, Qo, will (INCREASE, DECREASE, REMAIN THE SAME). (d) (10 Points) List two possible donor dopants: and and and two possible acceptor dopants