Accession Number : ADA118864

Title :   MNOS/SOS Radiation Hardness Performance and Reliability Study.

Descriptive Note : Interim rept. Aug 79-Aug 80,


Personal Author(s) : Hampton,F L ; Cricchi,J R

PDF Url : ADA118864

Report Date : May 1982

Pagination or Media Count : 165

Abstract : In this investigation the endurance-retention characteristics of fast-write MNOS memory structure, and radiation tolerance of metal-gate dual-dielectric and polysilicon-gate all-oxide devices have been evaluated. Writing and clearing speed have been studied with respect to the NH3:SiH4 ratio (APCVD), and NH3:SiC12H2 ratio (LPCVD). The films deposited with a low NH3:SiC12 ratios could be written and cleared with shorter pulse widths; however, a degradation in retention was observed. An improvement in the endurance retention product of a drain source protected transistor structure has been realized by oxidizing the memory nitride followed by an H2 anneal immediately after deposition. The film was deposited with a LPCVD reactor at 750 deg with a NH3:SiC12H2 ratio of 9:1. Oxidation was performed in steam at 900 C, as was the subsequent H2 anneal. The effect of total dose radiation was found to be more severe for a positive bias. The all oxide polysilicon gate transistor structures were observed to be relatively soft, however results from capacitor structures shows promise in developing a radiation tolerant polysilicon-gate all-oxide gate structure. (Author)

Descriptors :   *Gates(Circuits), *Semiconductors, *Memory devices, *Silicon, *Radiation hardening, Deposition, Dosage, Degradation, Velocity, Structures, Radiation tolerance, Capacitors, Reliability, Clearances, Endurance(General), Oxidation, Metals, Nitrides, Performance(Engineering), Radiation, Gamma rays, Bias, Radioactive isotopes, Retention(General), Cobalt

Subject Categories : Electrical and Electronic Equipment
      Nuclear Radiation Shield, Protection & Safety
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE