They are not producing hydrogen via electrolysis of water. They're utilizing an air plasma to oxidize some of the fuel before it is combusted. The water inlet/outlet in the plasmatron schematic are for a cooling jacket.
There's a similar article in EE times.
www.eetimes.com/story/OEG20010904S0028)
Sounds like they're using something called a "compliant substrate". The idea is that if the substrate is very thick relative to the film being grown then the tendency is for the film to deform it's lattice to match the substrate. The lattice strain stores energy, and as the film increases in thickness the amount of strain energy per unit volume of film increases. If the mismatch between substrate lattice dimensions and film dimensions is large enough the strain energy per unit volume can become large enough to nucleate dislocations at the interface. These dislocations allow the film to "relax" back to something near it's equilibrium lattice dimensions by periodically deleting or adding atomic planes near the interface. The problem is that these dislocations can thread up into the top of the film (i.e. where the device layers are) and act as non-radiative recombination centers and carrier traps. The dislocations can also jump from one layer to subsequently grown layers.
A compliant substrate tries to force the substrate to deform, and thus the strain E in the film never gets high enough to nucleate dislocations. For example, if you make the substrate very thin then as the film grows the substrate will deform to match the equilibrium lattice dimensions of the film rahter than the other way round. Traditionally in Si technology this has been done by ion implanting O2 in a thin layer some small distance below the surface fo the wafer. The wafer is then annealed to let the crystal structure recover from all the damage the ions did to the surface. This leaves a thin layer of "single crystal" silicon floating on a thin layer of glass. At growth temperatures of >1000 C in MOCVD the glass layer is fairly gooey, and the thin silicon layer practically floats on it. So as long as the epi film is thicker than the Si compliant substrate you're golden.
But this adds 2 steps to the production run, and ion implanting isn't generally a high throughput process. (i.e. $$$$$$$$$$$$$) Seems like Motorola's trick is to deposite a layer of some oxide with a crystal structure similar to GaAs. They then let oxygen diffuse down into the Si to form glass. So they bipass the implantation step.
The intermediate layer probably doesn't match the GaAs exactly anyway, which means you still get dislocations. Alot fo Motorola's research time and patents were probably devoted to converting existing techniques for reducing dislocation density to work with the intermediate layer material.
Anyway, I hope this gives you some idea of why I'm kinda skeptical. Old dog, maybe not-so-new tricks. But if Motorola has pulled it off it would be pretty sweet.
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They are not producing hydrogen via electrolysis of water. They're utilizing an air plasma to oxidize some of the fuel before it is combusted. The water inlet/outlet in the plasmatron schematic are for a cooling jacket.
silicon
There's a similar article in EE times. www.eetimes.com/story/OEG20010904S0028) Sounds like they're using something called a "compliant substrate". The idea is that if the substrate is very thick relative to the film being grown then the tendency is for the film to deform it's lattice to match the substrate. The lattice strain stores energy, and as the film increases in thickness the amount of strain energy per unit volume of film increases. If the mismatch between substrate lattice dimensions and film dimensions is large enough the strain energy per unit volume can become large enough to nucleate dislocations at the interface. These dislocations allow the film to "relax" back to something near it's equilibrium lattice dimensions by periodically deleting or adding atomic planes near the interface. The problem is that these dislocations can thread up into the top of the film (i.e. where the device layers are) and act as non-radiative recombination centers and carrier traps. The dislocations can also jump from one layer to subsequently grown layers. A compliant substrate tries to force the substrate to deform, and thus the strain E in the film never gets high enough to nucleate dislocations. For example, if you make the substrate very thin then as the film grows the substrate will deform to match the equilibrium lattice dimensions of the film rahter than the other way round. Traditionally in Si technology this has been done by ion implanting O2 in a thin layer some small distance below the surface fo the wafer. The wafer is then annealed to let the crystal structure recover from all the damage the ions did to the surface. This leaves a thin layer of "single crystal" silicon floating on a thin layer of glass. At growth temperatures of >1000 C in MOCVD the glass layer is fairly gooey, and the thin silicon layer practically floats on it. So as long as the epi film is thicker than the Si compliant substrate you're golden. But this adds 2 steps to the production run, and ion implanting isn't generally a high throughput process. (i.e. $$$$$$$$$$$$$) Seems like Motorola's trick is to deposite a layer of some oxide with a crystal structure similar to GaAs. They then let oxygen diffuse down into the Si to form glass. So they bipass the implantation step. The intermediate layer probably doesn't match the GaAs exactly anyway, which means you still get dislocations. Alot fo Motorola's research time and patents were probably devoted to converting existing techniques for reducing dislocation density to work with the intermediate layer material. Anyway, I hope this gives you some idea of why I'm kinda skeptical. Old dog, maybe not-so-new tricks. But if Motorola has pulled it off it would be pretty sweet.