초록 ▼

A single step method for boron dopant diffusion implementing both deposition and drive-in diffusions in one furnace process is provided. By using a spin-on dopant in a diffusion furnace with pyrogenic steam and thermal ramping capabilities, sheet resistivities and penetrations to a precision and acc

A single step method for boron dopant diffusion implementing both deposition and drive-in diffusions in one furnace process is provided. By using a spin-on dopant in a diffusion furnace with pyrogenic steam and thermal ramping capabilities, sheet resistivities and penetrations to a precision and accuracy of 4% with one furnace step are achievable. The one step method disclosed circumvents the use of two furnace processes to achieve a typical p-type diffusion which requires a deposition in a furnace set at one temperature followed by a drive in diffusion in a furnace set at a second temperature after deglazing in a hydrofluoric acid. Also attainable by the one step process disclosed are resistivity uniformities better than those with the two furnace processes.

대표청구항 ▼

A single furnace method for boron dopant deposition and diffusion of a p-type semiconductor substrates comprising: (a) applying a dopant layer to said semiconductor substrate from a gaseous dopant source until an initial resistivity in the range of about 4 to about 200 ohms per square is attained; (

A single furnace method for boron dopant deposition and diffusion of a p-type semiconductor substrates comprising: (a) applying a dopant layer to said semiconductor substrate from a gaseous dopant source until an initial resistivity in the range of about 4 to about 200 ohms per square is attained; (b) producing a conducting interfacial layer between said semiconductor substrate and said dopant layer by maintaining a temperature of at least about 900°C.; (c) removing said dopant source by maintaining a steam atmosphere of at least about 900°C.; (d) thermal ramping said treated semiconductor substrate to a drive in temperature for the doping in an atmosphere selected from inert, oxidizing or steam; (e) oxidizing excess silicon boride by subjecting said treated semiconductor substrate for about 5 to 20 minutes in a steam atmosphere at a temperature of the order of 1050°C. to 1250°C.; and (f) driving the boron present in said interfacial layer to the desired depth and resistivity level in an inert or oxidizing atmosphere.