Methods of forming microelectronic devices and related microelectronic devices, memory devices and electronic systems

A microelectronic device includes a stack structure, a step structure, a composite pad structure and a conductive contact structure. The stacked structure includes vertically alternating conductive structures and insulating structures arranged in a hierarchy. Each of the levels individually includes one of the conductive structures and one of the insulating structures. The step structure has steps including edges of at least some of the levels of the stacked structure. And the composite pad structure is arranged on the steps of the step structure. Each of the composite pad structures includes a lower pad structure and an upper pad structure overlying the lower pad structure and made of a material different from that of the lower pad structure. The conductive contact structure extends through the composite pad structure and to the conductive structure of the stack structure. Memory devices, electronic systems, and methods of forming microelectronic devices are also described. 一种微电子装置包括堆叠结构、阶梯结构、复合垫结构及导电接触结构。所述