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The author was reading about power use and transistor types. The entire article was neglecting to talk about the use of the low and stable and specifiable reverse bias break down voltage as a voltage limiter. You can buy a 20 volt Shottky, which means that its reverse bias break down voltage is 20 volts, and it can be used to bypass any higher voltage THROUGH the diode. There can be stablity issues, but as noted the Shottky is quite fast and its stable up to eg PWM, frequencies.
220.233.121.43 ( talk) 00:23, 8 November 2015 (UTC)
This (and corresponding part of the main article) seems wrong! Someone may have confused a Schottkey diode with a Zener diode.
86.26.2.112 ( talk) 16:09, 19 November 2015 (UTC)
'typically 300mv' conflicts with 'Schottky diodes have a drop of only about 0.2 volts.' in opening paragraph.
This article needs expanding with more detail and facts on metal-semiconductor contacts. Any takers?? Al
Whilst the diode does require lowered voltage this in turn means a reduction is temperature and so an increase in later resistance
Is it Schottky or Shottky? There is the Walter Shottky institute in Germany. Can anyone verify his real spelling? —The preceding unsigned comment was added by 65.209.67.191 ( talk) 20:51, 13 February 2007 (UTC).
-how do you pronounce 'schottky'?
- SHOT-key - RC Cola 20:35, 29 May 2006 (UTC)
Cree Inc. makes SiC schottky diodes with high Vr ratings. Specs for CSD20120 are: Vr 1200V, If(avg) 20A, Vf(typ) 1.6V @ 10A. CSD20120 Datasheet (PDF). — Ryan 23:45, 29 June 2006 (UTC)
It should be corrected that microwave mixers are commonly constructed using silicon schottky diodes for operation past 65 GHz. GaAs schottky diode mixers can be used well into the millimeter wave part of the spectrum...the wiki article indicates only to 5 GHz.
Why are there two applications sections? Nano Dan ( talk) 20:54, 12 July 2008 (UTC)
What about a V/I graph? I find those very useful. 151.61.26.186 ( talk) 16:21, 17 March 2009 (UTC)
The article now says "When current flows through a diode, it has some internal resistance to that current flow, which causes a small voltage drop across the diode terminals. A normal diode has between 0.7-1.7 volt drops...." Resistance doesn't correspond to a voltage drop without a specified current, so this must be wrong. I'm removing the wrong part, but something informative should be inserted 71.141.88.244 ( talk) 23:52, 23 April 2009 (UTC)
Yes. Well in formal text, it might be possible to refer to dV/dI. the ratio of the change in voltage for the change in current. This might confuse readers into thinking that higher level mathematics has been applied and there is a function that has been d/dx'd. So one might call it a slop, however with no voltage current curve, the author didn't want to refer to slope.. But yes you can call it resistance if Voltage = Diode drop + IR.... Or "impedance" is often used to refer to non-Ohmic operation... back EMF ? Hehe same thing. — Preceding unsigned comment added by 220.233.121.43 ( talk) 00:20, 8 November 2015 (UTC)
Too many editors who are not competant or experts. Needs a major clean up and re-org. It is such a fundemental component, deserves better. I really really do not like mention of commercial companies in the body of the article. A reference should be made to a published scientific article, not a commercial brochure or a copany web site. I will come back when have a chance. —Preceding unsigned comment added by 12.229.112.98 ( talk) 22:10, 19 February 2010 (UTC)
Agreed. Schottky barriers are damn cool things. If you read this article and the Schottky barrier article, you get the impression that the M/S junction just has some kind of rectifying feature with low voltage drop. This completely ignores the fact that way the Schottky barrier works, and the source of it's useful features, is quantum tunneling; hence the lower voltage drop (tunneled particles maintain kinetic energy; what voltage drop does occur is due to the reflection of some the particles at the potential barrier, and the redistribution of what charges make it through the M/S junction ). Although the Schottky barrier height is poorly understood, The Schottky Diode is an absolutely excellent example of how quantum physics effects the macro world, and how we can use the stranger features of quantum mechanics in many pieces of modern technology.
This article needs a rewrite by a physicist, not an electrical engineer. —Preceding unsigned comment added by 128.138.96.92 ( talk) 21:35, 24 February 2011 (UTC)
Please see the corresponding discussion thread at Wikipedia talk:WikiProject Electronics. Thanks! • Sbmeirow • Talk • 23:34, 15 December 2013 (UTC)
1. "This can be used for simultaneous formation of ohmic contacts and diodes, as diodes form between the silicide and lightly doped n-type region and ohmic contacts form between the silicide and a heavily doped n- or p-type region."
Too many ands ... the sentence should be improved.
2. "They also have forward voltage closer to that and require more attention in layout."
What is "that"? The pn junction voltage?
3. "The junction lies in direct contact to the thermally sensitive metallization, a Schottky diode can therefore dissipate less power than an equivalent-size p-n counterpart".
The first part of the sentence does not connect well with the rest of it. It needs to be improved.
4. "This "instantaneous" switching is not always the case."
I think there is a better way to phrase this.
5. "The Schottky diode models distributed by manufacturers are also often given without a valid TR parameter leading to an optimistic expectation."
Is that supposed to be trr?
6. "(BV, IR)".
What is BV? What is IR?
7. Germanium diodes are mentioned in the article. Then they are labeled as superseded. Are they actually used at this time? Isn't germanium technology obsolete? ICE77 ( talk) 03:20, 25 July 2015 (UTC)
Once again, User:VQuakr, you are reverting my edits for no good reason. You reverted the bold lines. Please explain why those lines do not belong in the article.
"Diodes act rather like one way valves that require sufficient pressure to open the valve and allow flow in that direction. When sufficient forward voltage (breakdown voltage) is applied, a current flows in the forward direction. A silicon diode has a typical breakdown voltage of 600–700 mV, while the Schottky's breakdown voltage is 150 – 450 mV. This lower breakdown voltage requirement allows higher switching speeds and better system efficiency. The reverse voltage needed to cause current conduction in the reverse direction is very much higher than for the forward direction."
Before I began work on the article, the paragraph originally read:
"When forward current flows through a solid-state diode, there is a small voltage drop across its terminals. A silicon diode has a typical voltage drop of 600–700 mV, while a Schottky diode has a voltage drop of 150 – 450 mV. This lower voltage drop can be used to give higher switching speeds and better system efficiency."
The above paragraph contains material that is complete rot. The current does not cause the voltage to appear, the breakdown voltage is applied and a nano second later the diode becomes conductive. To say otherwise is to put the cart before the horse. Yet you reverted my edit, suggesting that you agree with the original writing. I wonder, do you know anything of how diodes work? Zedshort ( talk) 16:06, 10 May 2016 (UTC)
I've added sample and hold circuits as another application. (with reference) TheUnnamedNewbie ( talk) 09:19, 9 January 2017 (UTC)
Someone seems to keep wanting to add mention of polyacetylene diodes. Certainly that is possible, there has been work on organic semiconductors for many years, and organic LEDs seem also to exist, but I don't believe it is the usual Schottky diode. Even so, if such devices exist, they might have a section in the article. Gah4 ( talk) 18:23, 30 March 2020 (UTC)
Small imprecision in the section Reverse recovery time. The text states in Schottky diodes there is nothing to recover from (i.e., there is no charge carrier depletion region at the junction). Actually there is charge depletion on the semiconductor side of a Schottky barrier and it depends on the bias, just like in a junction diode. Both pn and Schottky diodes have a junction capacitance C_J. The big difference is that pn diodes also have minority carrier diffusion and a diffusion capacitance C_D due to the stored minority carriers. In forward bias C_D is way larger than C_J and the true reason why pn diodes are slow: it takes a lot of time to remove those minority carriers and the diode stays ON for quite a while (on the scale of the recombination time). Possible reference: R.F.Pierret "Semiconductor Device Fundamentals", Chap.8 - pn Junction Diode: Transient Response. I am not editing the main article since I have never done that: I don't want to mess up! Wikirod76 ( talk) 13:10, 19 June 2020 (UTC)
Ok I edited the main article. Stating that Schottky diodes have no charge depletion (and the consequent junction capacitance) is incorrect. The reason why pn diodes are slow is that they have a (typically large) diffusion capacitance. In other words, they accumulate plenty of minority carriers in their diffusion region during the ON state, and it takes a lot of time to remove them. I added the reference too. The section might still need some clean up... my edit is somewhat repeated (majority carrier device, diffusion etc) in the last paragraph of the section (which was in contradiction with what stated in the first paragraph before my edit). I also notice that 200kHz-2MHz is indicated as a good range for "high-speed diodes", but Schottky can keep working well into the microwave spectral range..... Wikirod76 ( talk) 12:07, 21 June 2020 (UTC)
The History section only describes the inventor and another of his discoveries and nothing about the development or discovery of the diode. The article on Walter Schottky also describes nothing about the history of the diode.
Can anyone expand this section? Lkingscott ( talk) 10:36, 11 March 2023 (UTC)
This is the
talk page for discussing improvements to the
Schottky diode article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||
|
The author was reading about power use and transistor types. The entire article was neglecting to talk about the use of the low and stable and specifiable reverse bias break down voltage as a voltage limiter. You can buy a 20 volt Shottky, which means that its reverse bias break down voltage is 20 volts, and it can be used to bypass any higher voltage THROUGH the diode. There can be stablity issues, but as noted the Shottky is quite fast and its stable up to eg PWM, frequencies.
220.233.121.43 ( talk) 00:23, 8 November 2015 (UTC)
This (and corresponding part of the main article) seems wrong! Someone may have confused a Schottkey diode with a Zener diode.
86.26.2.112 ( talk) 16:09, 19 November 2015 (UTC)
'typically 300mv' conflicts with 'Schottky diodes have a drop of only about 0.2 volts.' in opening paragraph.
This article needs expanding with more detail and facts on metal-semiconductor contacts. Any takers?? Al
Whilst the diode does require lowered voltage this in turn means a reduction is temperature and so an increase in later resistance
Is it Schottky or Shottky? There is the Walter Shottky institute in Germany. Can anyone verify his real spelling? —The preceding unsigned comment was added by 65.209.67.191 ( talk) 20:51, 13 February 2007 (UTC).
-how do you pronounce 'schottky'?
- SHOT-key - RC Cola 20:35, 29 May 2006 (UTC)
Cree Inc. makes SiC schottky diodes with high Vr ratings. Specs for CSD20120 are: Vr 1200V, If(avg) 20A, Vf(typ) 1.6V @ 10A. CSD20120 Datasheet (PDF). — Ryan 23:45, 29 June 2006 (UTC)
It should be corrected that microwave mixers are commonly constructed using silicon schottky diodes for operation past 65 GHz. GaAs schottky diode mixers can be used well into the millimeter wave part of the spectrum...the wiki article indicates only to 5 GHz.
Why are there two applications sections? Nano Dan ( talk) 20:54, 12 July 2008 (UTC)
What about a V/I graph? I find those very useful. 151.61.26.186 ( talk) 16:21, 17 March 2009 (UTC)
The article now says "When current flows through a diode, it has some internal resistance to that current flow, which causes a small voltage drop across the diode terminals. A normal diode has between 0.7-1.7 volt drops...." Resistance doesn't correspond to a voltage drop without a specified current, so this must be wrong. I'm removing the wrong part, but something informative should be inserted 71.141.88.244 ( talk) 23:52, 23 April 2009 (UTC)
Yes. Well in formal text, it might be possible to refer to dV/dI. the ratio of the change in voltage for the change in current. This might confuse readers into thinking that higher level mathematics has been applied and there is a function that has been d/dx'd. So one might call it a slop, however with no voltage current curve, the author didn't want to refer to slope.. But yes you can call it resistance if Voltage = Diode drop + IR.... Or "impedance" is often used to refer to non-Ohmic operation... back EMF ? Hehe same thing. — Preceding unsigned comment added by 220.233.121.43 ( talk) 00:20, 8 November 2015 (UTC)
Too many editors who are not competant or experts. Needs a major clean up and re-org. It is such a fundemental component, deserves better. I really really do not like mention of commercial companies in the body of the article. A reference should be made to a published scientific article, not a commercial brochure or a copany web site. I will come back when have a chance. —Preceding unsigned comment added by 12.229.112.98 ( talk) 22:10, 19 February 2010 (UTC)
Agreed. Schottky barriers are damn cool things. If you read this article and the Schottky barrier article, you get the impression that the M/S junction just has some kind of rectifying feature with low voltage drop. This completely ignores the fact that way the Schottky barrier works, and the source of it's useful features, is quantum tunneling; hence the lower voltage drop (tunneled particles maintain kinetic energy; what voltage drop does occur is due to the reflection of some the particles at the potential barrier, and the redistribution of what charges make it through the M/S junction ). Although the Schottky barrier height is poorly understood, The Schottky Diode is an absolutely excellent example of how quantum physics effects the macro world, and how we can use the stranger features of quantum mechanics in many pieces of modern technology.
This article needs a rewrite by a physicist, not an electrical engineer. —Preceding unsigned comment added by 128.138.96.92 ( talk) 21:35, 24 February 2011 (UTC)
Please see the corresponding discussion thread at Wikipedia talk:WikiProject Electronics. Thanks! • Sbmeirow • Talk • 23:34, 15 December 2013 (UTC)
1. "This can be used for simultaneous formation of ohmic contacts and diodes, as diodes form between the silicide and lightly doped n-type region and ohmic contacts form between the silicide and a heavily doped n- or p-type region."
Too many ands ... the sentence should be improved.
2. "They also have forward voltage closer to that and require more attention in layout."
What is "that"? The pn junction voltage?
3. "The junction lies in direct contact to the thermally sensitive metallization, a Schottky diode can therefore dissipate less power than an equivalent-size p-n counterpart".
The first part of the sentence does not connect well with the rest of it. It needs to be improved.
4. "This "instantaneous" switching is not always the case."
I think there is a better way to phrase this.
5. "The Schottky diode models distributed by manufacturers are also often given without a valid TR parameter leading to an optimistic expectation."
Is that supposed to be trr?
6. "(BV, IR)".
What is BV? What is IR?
7. Germanium diodes are mentioned in the article. Then they are labeled as superseded. Are they actually used at this time? Isn't germanium technology obsolete? ICE77 ( talk) 03:20, 25 July 2015 (UTC)
Once again, User:VQuakr, you are reverting my edits for no good reason. You reverted the bold lines. Please explain why those lines do not belong in the article.
"Diodes act rather like one way valves that require sufficient pressure to open the valve and allow flow in that direction. When sufficient forward voltage (breakdown voltage) is applied, a current flows in the forward direction. A silicon diode has a typical breakdown voltage of 600–700 mV, while the Schottky's breakdown voltage is 150 – 450 mV. This lower breakdown voltage requirement allows higher switching speeds and better system efficiency. The reverse voltage needed to cause current conduction in the reverse direction is very much higher than for the forward direction."
Before I began work on the article, the paragraph originally read:
"When forward current flows through a solid-state diode, there is a small voltage drop across its terminals. A silicon diode has a typical voltage drop of 600–700 mV, while a Schottky diode has a voltage drop of 150 – 450 mV. This lower voltage drop can be used to give higher switching speeds and better system efficiency."
The above paragraph contains material that is complete rot. The current does not cause the voltage to appear, the breakdown voltage is applied and a nano second later the diode becomes conductive. To say otherwise is to put the cart before the horse. Yet you reverted my edit, suggesting that you agree with the original writing. I wonder, do you know anything of how diodes work? Zedshort ( talk) 16:06, 10 May 2016 (UTC)
I've added sample and hold circuits as another application. (with reference) TheUnnamedNewbie ( talk) 09:19, 9 January 2017 (UTC)
Someone seems to keep wanting to add mention of polyacetylene diodes. Certainly that is possible, there has been work on organic semiconductors for many years, and organic LEDs seem also to exist, but I don't believe it is the usual Schottky diode. Even so, if such devices exist, they might have a section in the article. Gah4 ( talk) 18:23, 30 March 2020 (UTC)
Small imprecision in the section Reverse recovery time. The text states in Schottky diodes there is nothing to recover from (i.e., there is no charge carrier depletion region at the junction). Actually there is charge depletion on the semiconductor side of a Schottky barrier and it depends on the bias, just like in a junction diode. Both pn and Schottky diodes have a junction capacitance C_J. The big difference is that pn diodes also have minority carrier diffusion and a diffusion capacitance C_D due to the stored minority carriers. In forward bias C_D is way larger than C_J and the true reason why pn diodes are slow: it takes a lot of time to remove those minority carriers and the diode stays ON for quite a while (on the scale of the recombination time). Possible reference: R.F.Pierret "Semiconductor Device Fundamentals", Chap.8 - pn Junction Diode: Transient Response. I am not editing the main article since I have never done that: I don't want to mess up! Wikirod76 ( talk) 13:10, 19 June 2020 (UTC)
Ok I edited the main article. Stating that Schottky diodes have no charge depletion (and the consequent junction capacitance) is incorrect. The reason why pn diodes are slow is that they have a (typically large) diffusion capacitance. In other words, they accumulate plenty of minority carriers in their diffusion region during the ON state, and it takes a lot of time to remove them. I added the reference too. The section might still need some clean up... my edit is somewhat repeated (majority carrier device, diffusion etc) in the last paragraph of the section (which was in contradiction with what stated in the first paragraph before my edit). I also notice that 200kHz-2MHz is indicated as a good range for "high-speed diodes", but Schottky can keep working well into the microwave spectral range..... Wikirod76 ( talk) 12:07, 21 June 2020 (UTC)
The History section only describes the inventor and another of his discoveries and nothing about the development or discovery of the diode. The article on Walter Schottky also describes nothing about the history of the diode.
Can anyone expand this section? Lkingscott ( talk) 10:36, 11 March 2023 (UTC)