Figure 1

(Color online) Schematic representation of the processes considered in our model [Eqs. (1a, 1b, 1c)]. The sketched species correspond to mobile species (ball model), islands (solid disks), and substrate (slab $M^0$). The represented processes are (from left to right) time-dependent flux $\left(\tilde{F}\right)$, nucleation and aggregation by diffusion of mobile species $\left(D_n\right)$, dissociation of species $\left({\Gamma }_n\right)$, species coarsening via direct incidence with atomic insertion $\left(I\right)$ or indirect incidence with capture in the surrounding area $A_n$ by transient mobility $\left({\mu }_T\right)$, re-evaporation of species $\left({\epsilon }_n\right)$, island coalescence $\left(\Phi \right)$, depletion of monomers around the islands $\left(\nabla {\rho }_n^1\right)$ where the depleted areas are encircled, and top-layer nucleation and aggregation $\left({\rho }_n^{k>1}\right)$.Reuse & Permissions

Figure 2

(Color online) (a) Pulsed flux [curve $F\left(t\right)$—with pulse width of $t_F=1\text{ms}$, frequency ${\nu }_F=1\text{Hz}$, and intensity $F/t_F{\nu }_F$ plotted in arb. unit] and $T$ transients [curves $T\left(t\right)$—with several pulse widths $\Delta t$ and amplitudes of $\Delta T=120\text{K}$ over a common base temperature of $T_0=753\text{K}$, so $\Delta T+T_0=873\text{K}$] used in the simulations of the pulsed growth kinetics. The $T$ transients are generated with a chopped ${\text{CO}}_2$ laser focused on YSZ surface [25, 27, 28]. (b) Thickness dependence of the roughness generated at constant $T=873\text{K}$ with the PVD techniques: MBE (solid line), PTD (▲), PLD (◼), and their fully pulsed counterparts: $\Delta t$-FPTD (△) and $\Delta t$-FPLD (◻) whose time-dependent growth temperatures correspond to the $T$ transients shown in (a). Sketches depict the representative morphologies of surface structures formed at $t=20\text{s}$ with PLD, FPTD, and FPLD (for $\Delta t=250\text{ms}$). The numbers correspond to cross sections per ML and $p$ denotes the slope at the structure border. (c) Time-width $\Delta t$ dependence of the roughness for a 3.0-ML-thick $\left(\approx 0.8\text{nm}\right)$ YSZ film grown by FPTD (△) or FPLD (◻). Note that for $\Delta t=0\text{s}$ $\left(\Delta t=1/{\nu }_F=1\text{s}\right)$, FPTD and FPLD produce similar results to those of PTD (▲) and PLD (◼) at constant $T=753\text{K}$ (const. $T=873\text{K}$), respectively.Reuse & Permissions

Figure 3

(Color online) (a) Dependences of the characteristic times of on-top incidence $\left(t_i^{pul}\right)$, escape downward $\left(t_r\right)$, and atomic exchange $\left(t_e\right)$ on the size of the involved largest species for various growth temperatures. The 2D and 3D morphologies of septamers generated at 873 and 813 K, respectively, are sketched by means of a ball model and the corresponding critical sizes $n_c^{2\text{D}\to 3\text{D}}$ are pointed out. The optimal time width $\Delta t=250\text{ms}$ of the $T$ transient (that satisfies the condition $t_r<\Delta t<t_e$ for $n\le n_c^{2\text{D}\to 3\text{D}}$) is indicated on the right margin. (b) Times of formation (and corresponding deposited thickness $F{\tau }_x$—right-hand axis) of $n$-sized species via the successive incidence of thermal $\left({\tau }_i^{th}\right)$ and hyperthermal $\left({\tau }_i^{hy}\right)$ atoms or via the atomic exchange $\left({\tau }_e\right)$. The vertical lines denote the values of the temperature-dependent $n_c^{2\text{D}\to 3\text{D}}=n_c\left(T\right)$. The optimal modulation amplitudes $\Delta T=120\text{K}$ and $\Delta T=60\text{K}$ of the $T$ transients for growths with thermal and hyperthermal pulsed fluxes, respectively, are indicated.Reuse & Permissions