Semiconductor Processing Single Crystal Silicon Professor Masoud Agah ECE Department

Crystal Structure Solid  in crystalline and amorphous forms Crystalline solids: constituent atoms of the solid are spatially arranged in periodic fashion. Crystalline solid  single crystal or polycrystalline Amorphous materials are devoid of long-range periodic structure.

Crystal Structure Lattice: the periodic arrangement of atoms in a crystal Unit cell: the smallest volume representing the lattice Simple Cubic (SC) Body-Centered Cubic (BCC) Face-Centered Cubic (FCC)

Crystal Structure Directions are expressed similar to vectors in [ ]. In a cubic lattice, [100] = [010] = [001]  <100>

Crystal Structure Deriving Miller indices to define a set of parallel planes: The intercepts of the plane with the crystal axes are found. The reciprocal of the three integers are taken. The smallest set of integers h, k, and l are found that have the same relationship to each other as the three reciprocals (1/4, 1/3, and 1/2 are converted to 3, 4, and 6). These integers are Miller indices of the plane, and the plane is labeled (h k l). Equivalent planes are labeled as {h k l}. In cubic cells, direction [h k l] is perpendicular to a plane (h k l).

Crystal Structure

Crystal Structure Silicon has a diamond cubic lattice. The diamond lattice also contains four lattice points per unit cell but contains 8 atoms per unit cell. The number of silicon atoms: 5x1022 atoms/cm3

SCS Manufacturing

SCS Manufacturing