CMOS-compatible metal-stabilized nanostructured Si as anodes for lithium-ion microbatteries.

Gibaek Lee,Stefan L Schweizer,Ralf B Wehrspohn

doi:10.1186/1556-276x-9-613

Abstract

The properties of fully complementary metal-oxide semiconductor (CMOS)-compatible metal-coated nanostructured silicon anodes for Li-ion microbatteries have been studied. The one-dimensional nanowires on black silicon (nb-Si) were prepared by inductively coupled plasma (ICP) etching and the metal (Au and Cu) coatings by successive magnetron sputtering technique. The Cu-coated nb-Si show the most promising electrochemical performance enhancements for the initial specific capacity as well as their cyclability compared to pristine nb-Si. The electrochemical and microstructural properties before and after cycling of the metal-coated nb-Si compared to their pristine counterparts are discussed in detail.

Highlights

Microbatteries are required to drive small devices, such as smartcards, medical implants, and sensors
In contrast to [16,17,18,19], we examine in this paper the potential of a fully complementary metal-oxide semiconductor (CMOS)-compatible technology for metal-coated 1-D nanowires on black silicon using inductively coupled plasma (ICP) etching and successive coating by metal magnetron sputtering
An intense signal of the metal was detected in the upper part, resulting from the fact that the metal elements can only penetrate into the top part of the nanowires on black silicon (nb-Si) due to the physical nature of the sputtering process

Summary

Introduction

Microbatteries are required to drive small devices, such as smartcards, medical implants, and sensors. The electrochemical performances of these all-solid-state batteries are limited because planar thin films are employed as electrode and electrolyte materials. The thickness of the stacking films is typically limited below 15 μm, and the resulting battery reveals relatively low power and energy densities. In order to develop improved electrochemical performances, new materials and complementary metal-oxide semiconductor (CMOS)compatible high-throughput manufacturing processes are required. Large specific area substrates by nanoarchitectured electrodes may represent a promising alternative to improve the general performances of these micro power sources [1,2,3]. Among various anode materials in lithium-ion battery, Si has the highest theoretical specific capacity (approximately 4,200 mAh g−1, Li4.4Si), has a low Li uptake potential (approximately 0.4 V vs Li/Li+), and is completely CMOS compatible [4,5]

Methods

Results

Conclusion