INJECTION-FIELD STRUCTURE MADE BY DOUBLE DIFFUSION OF IMPURITIES

Abstract

In the 80s of the last century, integrated injection logic (I2L) was widely used as an element base. Somewhat later, in the development of I2L, injection-field logic (IPL) appeared for the construction of VLSI. Both element bases are close in the degree of integration on a chip. An increase in the degree of integration into VLSI can be achieved using self-displacement of regions, in which the introduction of impurities of different types is carried out using a single boundary of the masking material. In this paper, this principle is used to create a vertical channel of a key field-effect transistor of IPL logic. In a p-type epitaxial film deposited on an n+-type substrate, an n-type region with a depth greater than the thickness of the epitaxial film is sequentially created first, and then impurity diffusion is performed in the same window with the creation of a region p-type. The gap between these n-type regions is the channel of the field-effect transistor being formed. Next, a shallow n+-type region is created that overlaps the channel, which is the drain region of a key field-effect transistor with a vertical channel, the p-type diffusion region is a gate, and the uniformly alloyed region of the epitaxial film performs the function of an injector. Branching along the outlet in this IPL structure is provided by placing several drains along the perimeter of the channel. Due to this geometry, the structure has a greater reproducibility of parameters compared to the basic design of the IPL. Topological variants of the implementation of the IPL cell and schemes based on it are considered: schemes 6 OR-NOT and Dt-trigger. The proposed design and technological version of the IPL cell can be recommended for creating VLSI of a high degree of integration