Programmable Charge Storage Transistor, an Array of Elevationally-Extending Strings of Memory Cells, Methods of Forming Si3Nx, Methods of Forming Insulator Material That is Between a Control Gate and Charge-Storage Material of a Programmable Charge-Storage Transistor, Methods of Forming an Array of Elevationally-Extending Strings of Memory Cells, a Programmable Charge-Storage Transistor Manufactured in Accordance with Methods, and an Array of Elevationally-Extending Strings of Memory Cells Man

A method of forming Si3Nx, where “x” is less than 4 and at least 3, comprising:

• decomposing silicon tetrachloride into at least two decomposition species;
• after the decomposing the silicon tetra chloride, contacting an outer substrate surface with the at least two decomposition species;
• and
• after the contacting the outer substrate surface, providing an N-comprising precursor to form a reaction product comprising Si3Nx, where “x” is less than 4 and at least 3.

A method of forming Si3Nx, where “x” is less than 4 and at least 3, comprising:

• providing a single Si-comprising precursor into a chamber;
• decomposing the single Si-comprising precursor into at least two decomposition species that are different from one another, wherein each of at least two of said different decomposition species comprises Si;
• after the decomposing the Si-precursor molecule, contacting an outer substrate surface with the at least two decomposition species;
• and
• after the contacting the outer substrate surface, contacting the attached species with a N-comprising precursor.

A method of forming Si3Nx, where “x” is less than 4 and at least 3, comprising:

• providing a single silicon- and chlorine-comprising precursor into a chamber, the single silicon- and chlorine-comprising precursor being selected from silicon tetrachloride, hexachlorodisilane and trichlorosilane;
• decomposing the silicon- and chlorine-comprising precursor molecule into at least two decomposition species that are different from one another at a temperature of at least 500° C., at least one of the decomposition species comprising Si that attaches to the outer substrate surface to comprise an attached species;
• and
• after contacting the decomposing, providing ammonia to form a reaction product comprising Si3Nx, where “x” no more than 3.90 and at least 3.