Nanochemistry at the atomic scale revealed in hydrogen-induced semiconductor surface metallization.
Passivation of semiconductor surfaces against chemical attack can be achieved by terminating the surface-dangling bonds with a monovalent atom such as hydrogen. Such passivation invariably leads to the removal of all surface states in the bandgap, and thus to the termination of non-metallic surfaces. Here we report the first observation of semiconductor surface metallization induced by atomic hydrogen. This result, established by using photo-electron and photo-absorption spectroscopies and scanning tunnelling techniques, is achieved on a Si-terminated cubic silicon carbide (SiC) surface. It results from competition between hydrogen termination of surface-dangling bonds and hydrogen-generated steric hindrance below the surface. Understanding the ingredient for hydrogen-stabilized metallization directly impacts the ability to eliminate electronic defects at semiconductor interfaces critical for microelectronics, provides a means to develop electrical contacts on high-bandgap chemically passive materials, particularly for interfacing with biological systems, and gives control of surfaces for lubrication, for example of nanomechanical devices.
Derycke
Vincent
V
Commissariat à l'Energie Atomique, Laboratoire Surfaces et Interfaces de Matériaux Avancés associé à l'Université de Paris-Sud/Orsay, DSM-DRECAM-SPCSI, Bâtiment 462, Saclay, 91191 Gif sur Yvette Cedex, France.
Soukiassian
Patrick G
PG
Amy
Fabrice
F
Chabal
Yves J
YJ
D'angelo
Marie D
MD
Enriquez
Hanna B
HB
Silly
Mathieu G
MG
D000327:Adsorption; D017554:Carbon Compounds, Inorganic / Q000737:chemistry*; D003461:Crystallography / Q000379:methods*; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D008422:Materials Testing / Q000379:methods*; D008670:Metals / Q000737:chemistry*; D008832:Microchemistry / Q000379:methods; D016252:Microscopy, Scanning Tunneling / Q000379:methods; D008958:Models, Molecular; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D012666:Semiconductors; D017655:Silicon Compounds / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods; D013499:Surface Properties
D017554:Carbon Compounds, Inorganic; D008670:Metals; D017655:Silicon Compounds; D006859:Hydrogen; C022088:silicon carbide