Enhancing electrostatic coupling in silicon quantum dot array by dual gate oxide thickness for large-scale integration

Abstract

We propose a structure with word/bit line control for a two-dimensional quantum dot array, which allows random access for arbitrary quantum dots with a small number of control signals. To control multiple quantum dots with a single signal, every quantum dot should have a wide operating voltage allowance to overcome the property variations. We fabricate two-dimensional quantum dot arrays using silicon-complementary-metal-oxide-semiconductor technology with an alternating dual-standard gate oxide thickness. The quantum dots are designed to have an allowable operating voltage window of 0.2 V to control the number of electrons, which is a window one order of magnitude wider than that of previous works. The proposed structure enables both easy fabrication and operation for multiple quantum dots and will pave the way for practical use of large-scale quantum computers.