The effect of emitter junction bias on the low dose-rate radiation response of bipolar devices

The aim of this pa per is ap ply ing sta tis ti cal laws and en large ment law to de ter mine a re dundancy level of nanotechnology com put ers with a pre-given sta tis ti cal con fi dence. We have tested ra di a tion hard ness of MOS mem ory com po nents (com mer cial EPROM mem ory) using both Monte Carlo sim u la tion method and ex per i men tal pro ce dure. Then, by us ing the sta tis ti cal en large ment law, we have per formed the anal y sis of re dun dancy op ti mi za tion of MOS struc ture for nanotechnology com put ers, un der the in flu ence of back ground ra di a tion, and ob tained more than sat is fy ing re sults.

Section: Resultsmentioning

confidence: 99%

Monte Carlo optimization of redundancy of nanotechnology computer memories in the conditions of background radiation

Dolicanin

Fetahovic

2018

“…A rise in the concen tra tion of in ter face traps in creases ex cess base current both in npn and pnp tran sis tors, while in the pnp tran sis tors the in ter face traps af fect the base cur rent rise (and, there fore, the pnp tran sis tor's deg ra da tion), whence the ox ide-trapped charge (above the base area) sup presses the neg a tive ef fects of the in ter face traps [27]. Since the con cen tra tion of the oxide-trapped charge in creases ex po nen tially with the to tal dose [28] (con trary to the in ter face traps con centra tion, which in creases lin early with the ab sorbed dose [28]), it will cause a sharp ex po nen tial rise in the ex cess base cur rent of the af fected npn tran sis tors. There fore, the qui es cent cur rent, as a sum mary sup ply cur rent of all the el e men tary tran sis tors in the volt age reg u la tor con trol cir cuit, will di rectly rep li cate the sum mary ef fects of the trapped charge in the ox ide and at in ter faces.…”

Section: Discussionmentioning

confidence: 99%

Rapid and long-term gamma-radiation annealing in low-dropout voltage regulators

Vukić

2017

Sam ples of four types of low-drop out volt age reg u la tors, with both se rial pnp and npn transis tors, were ex am ined in room-tem per a ture iso ther mal gamma ra di a tion an neal ing. Af ter un in ter rupted ex po sure to a to tal ion is ing dose of 500 Gy, bi ased and loaded volt age reg u lators were ex am ined in room-tem per a ture an neal ing within the first 30 min utes af ter the expo sure. Be side the on-line mea sure ment of out put volt age and qui es cent cur rent dur ing the thirty-min ute pe riod im me di ately af ter ir ra di a tion, also re sults were pro cured af ter 10-year room-tem per a ture spon ta ne ous re cov ery. Data ob tained dur ing the ir ra di a tion and rapid anneal ing were fit ted with lin ear, ex po nen tial, and power-law re gres sion func tions. A sim ple pro ce dure was pro posed, based on the qui es cent cur rent an neal ing fac tor, for the quick es tima tion of the in te grated volt age reg u la tor's ra di a tion sen si tiv ity dur ing the post-ir ra di a tion iso ther mal an neal ing. In or der to es ti mate the cir cuit's ra di a tion sen si tiv ity, im me di ately af ter ir ra di a tion, tested de vices have to be left in the same op er at ing con di tions as dur ing the ex posure. If a clear trend of the qui es cent cur rent re cov ery can be ob served, fur ther ex am i na tions have to be im ple mented to es ti mate if a cir cuit is ac cept ably ra di a tion-tol er ant. If no re cov ery trend can be ob served within the first hour af ter ir ra di a tion, or even fur ther deg ra da tion is no ticed, then the ex am ined volt age reg u la tor is a ra di a tion-sen si tive de vice and can not be used in ra di a tion en vi ron ments. The de scribed pro ce dure is based on the mac ro scopic ef fects of the ra di a tion-in duced charge-trap ping in field ox ides and in ter faces. Key words: volt age reg u la tor, gamma ra di a tion, qui es cent cur rent, an neal ing fac tor, iso ther mal an neal ing, post-ir ra di a tion ef fect, re gres sion anal y sis V. Dj. Vuki}.: Rapid and Long-Term Gamma-Ra di a tion An neal ing in ...

“…Im me di ately af ter the start of ir ra di a tion the gener a tion of ox ide and in ter face traps be gins [22]. Accepted hy poth e sis is that an in crease in the in ter face trap con cen tra tion (N it ) in duces deg ra da tion of the lateral pnp tran sis tor, while the rise in ox ide trap con centra tion (N ot ) above the base area re duces the neg a tive ef fect of the in ter face traps on the in crease in a pnp tran sis tor's base cur rent, ac cord ing to ex pres sion [23]…”

Section: Re Sults and Discussionmentioning

confidence: 99%

Minimum dropout voltage on a serial pnp transistor of a moderately loaded voltage regulator in a gamma radiation field

Vukić

2012

The main examined value in an experiment performed on moderately loaded voltage regulators was the serial pnp transistor’s minimum dropout voltage, followed by the data on the base current and forward emitter current gain. Minimum dropout voltage decreased by up to 12%, while the measured values of the forward emitter current gain decreased by 20-40% after the absorption of a total ionizing dose of 500 Gy. The oxide trapped charge increased the radiation tolerance of the serial lateral pnp transistor owing to the suppression of interface trap formation above the base area. Current flow through the serial transistor of the voltage regulator had an influence on the decrease in the power pnp transistor’s forward emitter current gain. Due to the operation with a moderate load of 100 mA, loss of emitter injection efficiency was not as important as during the operation with high current density, thus eliminating the negative influence of emitter crowding on the radiation hardness of the voltage regulator. For a moderate load, gain in the negative feedback reaction was enough to keep output voltage in the anticipated range. Only information procured from tests of the minimum dropout voltage on the moderately loaded voltage regulators were not sufficient for unequivocal determination of the examined integrated circuit’s radiation hardness. [Projekat Ministarstva nauke Republike Srbije, br. 171007: Physical and functional effects of the interaction of radiation with electrical and biological systems