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Radiation effects on 2n2222 or similar

Started by Robert Baer June 29, 2019
   Placing the working unit (open base) in a very high dose area for 2 
months, where it will see approximately a rate of approximately 15 Rem/hour.
   Not steady state, but plenty every day.

   In the Apollo daze, some data may have been collected concerning this 
question (uA709 W-stepping, input pair).

   Is there any data concerning E-B zener voltage changes, and is there 
any material difference WRT transistor type (say 2N3904)?

   Thanks.
On 6/29/19 2:23 AM, Robert Baer wrote:
>   Placing the working unit (open base) in a very high dose area for 2 > months, where it will see approximately a rate of approximately 15 > Rem/hour. >   Not steady state, but plenty every day. > >   In the Apollo daze, some data may have been collected concerning this > question (uA709 W-stepping, input pair). > >   Is there any data concerning E-B zener voltage changes, and is there > any material difference WRT transistor type (say 2N3904)? > >   Thanks.
There are some degredation curves for common components given on p. 235 in this whitepaper from the Voyager program, looks like: <https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720018918.pdf> one from around the same time for neutron flux, military, stats-math-heavy: <https://apps.dtic.mil/dtic/tr/fulltext/u2/a065162.pdf> Foreign paper (Malaysia), x-rays: <http://www.jcomputers.us/vol9/jcp0909-26.pdf> The first two look somewhat relevant but this data is pushing 40 years old. how relevant is it to bjts made using modern process? How accurate was it to begin with? there is probably more recent/detailed info out there but it sounds like the kind of thing that might require a clearance. Could always do a FOIA request to the DOE as it's quite specific what you're looking for see if there's anything unclassified or no longer classified they might be willing to release. another one from JPL that's mid 90s vintage, looks like, very topical but it's pretty bare-bones with respect to data, couple crappy graphs: <https://pdfs.semanticscholar.org/762a/54443600250706f4d73e07aab7b126de9383.pdf> "Recent experience on the Cassini spacecraft project has shown that some bipolar devices exhibit large decreases in gain at low total dose levels, severely impacting their use in space. Figure 1 compares gain degradation of two small signal transistors, measured at the lowest collector current in the manufacturer&rsquo;s specifications. The 2N918 transistor exhibits only small changes in gain with total dose, while the 2N3700 is severely degraded, even at levels below 10 krad(Si). The gain loss is so severe that it is extremely difficult to use this device on the project, which must operate at levels between 50-100 krad(Si). This extreme degradation was not observed for earlier lots fl om the same manufacturer, and was greater than anticipated for any bipolar transistor with standard construction and normal breakdown voltage requirements."
On 6/29/19 2:02 AM, bitrex wrote:
> On 6/29/19 2:23 AM, Robert Baer wrote: >> &nbsp;&nbsp; Placing the working unit (open base) in a very high dose area for 2 >> months, where it will see approximately a rate of approximately 15 >> Rem/hour. >> &nbsp;&nbsp; Not steady state, but plenty every day. >> >> &nbsp;&nbsp; In the Apollo daze, some data may have been collected concerning >> this question (uA709 W-stepping, input pair). >> >> &nbsp;&nbsp; Is there any data concerning E-B zener voltage changes, and is >> there any material difference WRT transistor type (say 2N3904)? >> >> &nbsp;&nbsp; Thanks. > > There are some degredation curves for common components given on p. 235 > in this whitepaper from the Voyager program, looks like: > > <https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720018918.pdf> > > one from around the same time for neutron flux, military, stats-math-heavy: > > <https://apps.dtic.mil/dtic/tr/fulltext/u2/a065162.pdf> > > Foreign paper (Malaysia), x-rays: > > <http://www.jcomputers.us/vol9/jcp0909-26.pdf> > > > The first two look somewhat relevant but this data is pushing 40 years > old. how relevant is it to bjts made using modern process? How accurate > was it to begin with? there is probably more recent/detailed info out > there but it sounds like the kind of thing that might require a clearance. > > Could always do a FOIA request to the DOE as it's quite specific what > you're looking for see if there's anything unclassified or no longer > classified they might be willing to release. > > another one from JPL that's mid 90s vintage, looks like, very topical > but it's pretty bare-bones with respect to data, couple crappy graphs: > > <https://pdfs.semanticscholar.org/762a/54443600250706f4d73e07aab7b126de9383.pdf> > > > "Recent experience on the Cassini spacecraft project has shown that some > bipolar devices exhibit large decreases in gain at low total dose > levels, severely impacting their use in space. Figure 1 compares gain > degradation of two small signal transistors, measured at the lowest > collector current in the manufacturer&rsquo;s specifications. The 2N918 > transistor exhibits only small changes in gain with total dose, while > the 2N3700 is severely degraded, even at levels below 10 > krad(Si). > > The gain loss is so severe that it is extremely difficult to use this > device on the project, which must operate at levels between 50-100 > krad(Si). This extreme degradation was not observed for earlier lots fl > om the same manufacturer, and was greater than anticipated for any > bipolar transistor with standard construction and normal > breakdown voltage requirements."
one of the other unfortunate take-aways from the final paper is that damage profile can apparently vary widely even among the same generic type from different manufacturers.
Robert Baer wrote...
> > Placing the working unit (open base) in a very > high dose area for 2 months, where it will see > approximately a rate of approximately 15 Rem/hour.
What's a convenient way to get a "high dose area"? When in college (long ago) I had ready access to a nuclear reactor, and all kinds of sources, but ... -- Thanks, - Win
On Saturday, 29 June 2019 08:46:54 UTC+1, Winfield Hill  wrote:
> Robert Baer wrote... > > > > Placing the working unit (open base) in a very > > high dose area for 2 months, where it will see > > approximately a rate of approximately 15 Rem/hour. > > What's a convenient way to get a "high dose area"? > When in college (long ago) I had ready access to a > nuclear reactor, and all kinds of sources, but ...
David Hahn used smoke alarms for alphas. An x-ray tube is also possible.
On 6/29/19 3:46 AM, Winfield Hill wrote:
> Robert Baer wrote... >> >> Placing the working unit (open base) in a very >> high dose area for 2 months, where it will see >> approximately a rate of approximately 15 Rem/hour. > > What's a convenient way to get a "high dose area"? > When in college (long ago) I had ready access to a > nuclear reactor, and all kinds of sources, but ... > >
Part of the takeaway from this paper I posted from the 90s seems to be that performance can vary widely even among devices of the same generic type because it's highly dependent on emitter geometry/construction (does base metallization pass over the emitter-base region in a given jellybean? sometimes yes and sometimes no apparently, there's no "reference topology" as it were for those parts) and different manufacturers have different ways of doing things. or even the same manufacturer uses somewhat different geometries and construction on different runs. They're cheap parts they prolly press into service whatever slack capacity they have at a given time with whatever process the plant that's slack happens to be set up for, I don't think e.g. Fairchild has dedicated lines to cranking out jellybean 2N3904s anymore. <https://pdfs.semanticscholar.org/762a/54443600250706f4d73e07aab7b126de9383.pdf> There may be data on what particular mfgr as of 2019 makes the most resilient jellybeans off-the-shelf, it sounds like kind of info that perhaps reads class-i-fied
On Friday, June 28, 2019 at 10:23:41 PM UTC-7, Robert Baer wrote:
> Placing the working unit (open base) in a very high dose area for 2 > months, where it will see approximately a rate of approximately 15 Rem/hour.
> Is there any data concerning E-B zener voltage changes, and is there > any material difference WRT transistor type (say 2N3904)?
There's not a lot of consistency; a different metallization may cause an X-ray fluorescence, so the KIND of radiation matters as much as the ion-pair-production Rem number.
On 29/06/2019 07:23, Robert Baer wrote:
> In the Apollo daze, some data may have been collected concerning this > question (uA709 W-stepping, input pair).
I think the Apollo program used uA702. The uA709 came too late? piglet
On 29/06/2019 18:56, Piglet wrote:
> On 29/06/2019 07:23, Robert Baer wrote: >> In the Apollo daze, some data may have been collected concerning this >> question (uA709 W-stepping, input pair). > > I think the Apollo program used uA702. The uA709 came too late? > > piglet > > >
Answering myself: the uA709 was indeed used in some of the later lunar surface science packages. Makes sense as it was much nicer to use :) piglet
On Saturday, June 29, 2019 at 1:23:41 AM UTC-4, Robert Baer wrote:
> Placing the working unit (open base) in a very high dose area for 2 > months, where it will see approximately a rate of approximately 15 Rem/hour. > Not steady state, but plenty every day. > > In the Apollo daze, some data may have been collected concerning this > question (uA709 W-stepping, input pair). > > Is there any data concerning E-B zener voltage changes, and is there > any material difference WRT transistor type (say 2N3904)? > > Thanks.
>What's a convenient way to get a "high dose area"?
When in college (long ago) I had ready access to a nuclear reactor, and all kinds of sources, but ... Got a friend in the nuclear medicine field?