Title :
Impact of arsenic deactivation in polycrystalline silicon and at polysilicon-monosilicon interfaces on contact resistance
Author :
Perera, A.H. ; Taylor, W.J. ; Orlowski, M.
Author_Institution :
Adv. Products Res. & Dev. Lab., Motorola Inc., Austin, TX, USA
Abstract :
Arsenic deactivation in polycrystalline silicon, and in devices incorporating polysilicon in a 4 M SRAM BiCMOS process has been studied. The effects of anneal conditions and material characteristics (grain size and interfacial oxide) on sheet and contact resistance data, and npn bipolar characteristics, shows that arsenic deactivation in polysilicon and at poly/mono-silicon interfaces is a partially reversible process. Our data indicates that appropriate rapid thermal anneals can significantly reduce contact resistance (39%) and improve device performance by reactivating arsenic at the poly/mono-silicon interface.<>
Keywords :
BiCMOS integrated circuits; SRAM chips; annealing; arsenic; contact resistance; elemental semiconductors; integrated circuit technology; rapid thermal processing; semiconductor doping; semiconductor junctions; silicon; 4 M SRAM BiCMOS process; 4 Mbit; Si:As-Si; arsenic deactivation; contact resistance; grain size; interfacial oxide; npn bipolar characteristics; polycrystalline silicon; polysilicon-monosilicon interfaces; rapid thermal anneals; sheet resistance; BiCMOS integrated circuits; Contact resistance; Furnaces; MOSFET circuits; Random access memory; Rapid thermal annealing; Sheet materials; Silicon; Temperature; Thermal resistance;
Conference_Titel :
Electron Devices Meeting, 1993. IEDM '93. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-1450-6
DOI :
10.1109/IEDM.1993.347270
