Method of formation of nanocrystals on a semiconductor structure

A method of forming nanocrystals comprising:

• elevating a temperature of a substrate within a chamber to a first temperature in a range sufficient to react a precursor gas on a surface of the substrate within the chamber, while maintaining walls of the chamber at a second temperature substantially lower than the first temperature;
• flowing a co-flow gas at a sufficient flow rate within the chamber and maintaining a process pressure in order to form and maintain a thermal boundary layer overlying the surface of the substrate by maintaining a ratio of a mean free path of gas molecules of the co-flow gas to chamber dimensions to be less than one;
• introducing the precursor gas as a reactant gas into the chamber, wherein a portion of the precursor gas partially dissociates within the thermal bound layer;
• forming nanocrystals overlying the surface of the substrate in response to exposing the substrate to a partial dissociation of the precursor gas within the thermal boundary layer within the chamber.

A method of forming nanocrystals comprising:

• elevating a temperature of a substrate within a chamber to a first temperature in a range sufficient to react a precursor gas on a surface of the substrate within the chamber, while maintaining walls of the chamber at a second temperature substantially lower than the first temperature;
• flowing a co-flow gas at a sufficient flow rate within the chamber and maintaining a process pressure in order to form and maintain a thermal boundary layer overlying the surface of the substrates;
• introducing the precursor gas as a reactant gas into the chamber, wherein a portion of the precursor gas partially dissociates within the thermal boundary layer;
• forming nanocrystals overlying the surface of the substrate in response to exposing the substrate to a partial dissociation of the precursor gas within the thermal boundary layer within the chamber;
• annealing the nanocrystals by exposing the surface of the substrate to an inert gas flow at a third temperature higher than the first temperature;
• and
• cooling the substrate.

A method of forming nanocrystals comprising:

• elevating a temperature of a substrate within a chamber to a first temperature in a range sufficient to react a precursor gas on a surface of the substrate within the chamber, while maintaining walls of the chamber at a second temperature substantially lower than the first temperature, wherein the second temperature is at least 100 degrees Celsius lower than the first temperature;
• flowing a co-flow gas at a sufficient flow rate within the chamber and maintaining a process pressure in order to form and maintain a thermal boundary layer overlying the surface of the substrate;
• introducing the precursor gas as a reactant gas into the chamber, wherein a portion of the precursor gas partially dissociates within the thermal boundary layer;
• and
• forming nanocrystals overlying the surface of the substrate in response to exposing the substrate to partial dissociation of the precursor gas within the thermal boundary layer within the chamber, wherein the substrate includes a silicon substrate having a dielectric layer overlying the surface of the substrate, further wherein forming nanocrystals overlying the substrate surface includes forming nanocrystals on the dielectric layer, further wherein the dielectric layer includes silicon dioxide, and a by-product of the partial dissociation includes an active radical silylene that has a substantially unity sticking coefficient on a SiO2 surface of the dielectric layer, wherein the active radical silylene provides a source of silicon for forming nanocrystals through nucleation, wherein forming the nanocrystals includes forming silicon adatoms substantially from the active radical silylene, forming silicon nuclei from the silicon adatoms;
• and forming silicon nanocrystals from the silicon nuclei, further wherein the first temperature is substantially between 400 and 550 degrees Celsius, further wherein the precursor gas is introduced into the chamber at a sufficient flow rate to maintain a desired partial pressure of the precursor gas, wherein the desired partial pressure of the precursor gas is substantially in the range of 10 to 200 mTorr, further wherein the process pressure is substantially on the order of 1 to 100 Torr.

A method of forming nanocrystals comprising:

• elevating a temperature of a substrate within a cold wall CVD chamber to a first temperature in a range sufficient to react a precursor gas on a surface of the substrate within the cold wall CVD chamber, while maintaining walls of the cold wall CVD chamber at a second temperature substantially lower than the first temperature, wherein the second temperature is at least 100 degrees Celsius lower than the first temperature;
• flowing a co-flow gas at a sufficient flow rate within the cold wall CVD chamber and maintaining a process pressure in order to form and maintain a thermal boundary layer overlying the surface of the substrate;
• introducing the precursor gas as a reactant gas into the cold wall CVD chamber, wherein a portion of the precursor gas partially dissociates within the thermal boundary layer, wherein the precursor gas includes any metal containing gas;
• and
• forming nanocrystals overlying the surface of the substrate in response to exposing the substrate to partial dissociation of the precursor gas within the thermal boundary layer within the cold wall CVD chamber.

A method of forming nanocrystals comprising:

• elevating a temperature of a substrate within a chamber to a first temperature in a range sufficient to react a precursor gas on a surface of the substrate within the chamber, while maintaining walls of the chamber at a second temperature substantially lower than the first temperature;
• flowing a co-flow gas at a sufficient flow rate within the chamber and maintaining a process pressure in order to four and maintain a gaseous state thermal boundary layer overlying the surface of the substrate, the gaseous state thermal boundary having a first boundary overlying the substrate and having approximately the first temperature, the gaseous state thermal boundary having a second boundary overlying the first boundary and below an upper inner surface of the chamber, the second boundary of the gaseous state thermal boundary having a third temperature that is approximately equal to temperature at an inlet of the chamber;
• introducing tie precursor gas as a reactant gas into the chamber, wherein a portion of the precursor gas partially dissociates within the gaseous state thermal boundary layer;
• and
• forming nanocrystals overlying the surface of the substrate in response to exposing the substrate to a partial dissociation of the precursor gas within the gaseous state thermal boundary layer within the chamber.