The origin of extended dislocations induced by high-dose ion implantation
The origin and the generation mechanism of ion implantation-induced dislocations is investigated with an Si/sub 3/N/sub 4/ band line/space pattern. The Si/sub 3/N/sub 4/ film-edge stress not only causes dislocation propagation but also causes the formation and deformation of extended dislocations at the initial stage of annealing. The behavior is clarified that the dislocation loops are deformed into pattern-edge dislocation half loops, which accumulate at the film edge and are punched out from the edge.
A generalized approach for solution to image stresses of dislocations
Abstract This paper proposes an adaptive meshfree method to calculate the image stresses of the dislocations at the free boundaries and bicrystal interfaces. Based on the superposition method (van der Giessen and Alan Needleman, 1995) originally proposed for single crystal material with free boundaries, a weak formulation is developed for the bicrystal materials containing dislocations, where the interface constraints are imposed using Lagrangian multiplier. The meshfree approximation is introduced to improve the accuracy and smoothness from conventional FEM interpolation functions, and it is straightforward to adaptively enrich meshfree nodes at the surrounding area of dislocations to effectively improve the solution accuracy. The numerical examples demonstrate the effectiveness of the proposed method to calculate the image stress in 2D and 3D problems with various boundary and interface conditions using either the classical elasticity (J.P.Hirth and J.Lothe, 1982) or the singularity-free dislocation theory (M.Lazar, 2012, 2013, 2014; G.Po and M.Lazar, 2014).
Recoil oxygen implants and thermal redistribution of oxygen in through‐oxide arsenic‐implanted Si
The redistribution of recoil oxygen implants produced by the implantation of As ions through oxide layers on Si substrates has been investigated at annealing temperatures in the range 4000–1000 °C. Using transmission electron microscopy and secondary ion mass spectrometry profiling, it has been shown that the implanted (recoil) oxygen is rapidly gettered into residual damage structure at anneal temperatures < 900 °C. At temperatures ⩾ 1000 °C residual damage gettering sites are annihilated, releasing oxygen to migrate toward the Si surface. At the higher‐annealing temperatures, oxygen has been shown to outdiffuse rapidly into the overlying (1000 A) oxide layer on the sample surface.