Analytical Approach to Model and Diagnostic Distribution of Dopant in an Implanted-Heterojunction Rectifier Accounting for Mechanical Stress

We calculate spatiotemporal distributions of dopant in an implanted-heterojunction rectifier. We analyzed the influence of inhomogeneity of heterostructure on dopant distribution. The influence of radiation processing of materials of the heterostructure, which has been done during ion implantation, on properties of the heterostructure has been also analyzed. It has been shown that radiation processing of materials of heterostructure leads to a decrease in mechanical stress in heterostructure. Our calculations have been done by using analytical approach, which gives us the possibility to obtain all results without joining solutions on all interfaces of heterostructure. 1. Introduction In the present time one can find intensive development of devices of solid state electronic devices. One way to this development is increasing of frequency of switching of p-n-junctions [1–3]. To solve this problem it could be new search materials with higher charge carriers mobility [4–7]. Another way to decrease switching time is increasing sharpness of p-n-junctions [8, 9]. It has been recently shown that manufacturing diffusing- or implanted-junction rectifiers in a heterostructure ( ) and optimization time of annealing of dopant and/or radiation defects give us possibility to increase sharpness of p-n-junctions [10–12]. It is known that in any one could find mechanical stress. The strain arising due to mismatch of lattice distance in layers of ？？[13, 14]. Let us consider the following situation for simultaneous decreasing of mechanical stress and increasing of sharpness of p-n-junctions. We consider a with two layers, which consist of a substrate ( ) and an epitaxial layer (EL), with known type of conductivity: n or p (see Figure 1). A dopant has been implanted in the through the EL. The dopant produces the type of conductivity of , which reverses in comparison with type of conductivity of EL. In this situation we consider such conditions of implantation, under which major portion of dopant will be implanted in the . Further annealing of radiation defects has been considered. The main aim of the present paper is to determine the conditions, under which the mechanical stress in the will be decreased and at the same time sharpness of the p-n-junction will be increased. Figure 1: Heterostructure, which consists of substrate and epitaxial layer. 2. Method of Solution To solve our aims let us determine spatiotemporal distribution of dopant. We determine the distribution by solving the second Fick’s law [1–3] with boundary and initial conditions Here is the spatiotemporal