A kind of preparation method of memory unit

Abstract

The invention provides a method for preparing a memory cell, which includes performing a ring-shaped implantation process on the memory cell. The ring-shaped implantation process includes forward implantation and reverse implantation, wherein the number of gains and losses of the outermost layer of reverse implanted ions is the same as In contrast to forward implantation of ions, the ions are implanted into the device channel. In the method for preparing memory cells provided by the present invention, the reverse implantation method is added to the circular implantation process during the preparation of floating body effect memory cells, and the current carrying capacity is enhanced at the drain end while keeping the total implantation dose constant. The impact ionization rate between electrons and impurity scattering centers, thereby increasing the substrate current of the floating body effect memory cell, and improving the writing speed of the floating body effect memory cell.

Description

technical field [0001] The invention relates to the field of semiconductor preparation, in particular to a preparation method capable of improving the writing speed of a floating body DRAM. Background technique [0002] The development of embedded dynamic memory technology has made large-capacity DRAM very common in current system-on-chip (SOC). Large-capacity embedded dynamic memory (eDRAM) brings various benefits to SOCs, such as improved bandwidth and reduced power consumption, that can only be realized by using embedded technology. In addition to the transistor, each storage unit of the traditional embedded dynamic memory needs a deep trench capacitor structure. The deep trench of the capacitor makes the height of the storage unit much larger than its width, which makes the manufacturing process difficult. Its manufacturing process is very incompatible with CMOS VLSI process, which limits its application in embedded system-on-chip (SOC). [0003] Floating Body Cell (FB...

AI Technical Summary

Problems solved by technology

Due to the existence of the oxygen buried layer, the substrate current cannot be released, so that the holes accumulate in the floating

Images