FIELD

Embodiments of the present disclosure generally relate to a method of forming a thin film transistor (TFT), and more specifically to methods for forming a TFT having an indium gallium zinc oxide (IGZO) layer.

BACKGROUND

Metal oxide semiconductors, such as indium gallium zinc oxide (IGZO) are attractive for device fabrication due to high carrier mobility, low processing temperatures, and optical transparency. Front-End-of-Line (FEOL) or Back-end-of-line (BEOL) transistors include metal oxide semiconductors including indium gallium zinc oxide (IGZO) and may be useful in e.g., memory applications. The indium gallium zinc oxide (IGZO) material enables BEOL transistors for memory applications with low or zero leakage and relatively high mobility.

However, metal oxide layers, such as metal oxide channel layers including indium gallium zinc oxide (IGZO) are problematically susceptible to post-deposition processing deficiencies where hydrogen contributes to the formation of oxygen vacancies in the layer making the channel problematically conductive. Oxygen vacancies problematically lead to unstable semiconductor devices and are detrimental to the switching voltage of the devices. In addition, the formation of oxygen vacancies also causes negative threshold voltages, since oxygen vacancies are donors in metal oxide materials.

Therefore, the inventors believe that there is a need in the art for forming stable metal oxide materials such as indium gallium zinc oxide (IGZO) materials for use as a channel oxide layer.

SUMMARY

Methods and apparatus for passivating oxygen vacancy formation within amorphous indium gallium zinc oxide are provided herein. In some embodiments, a method for passivating oxygen vacancy formation within amorphous indium gallium zinc oxide, includes: depositing an amorphous indium gallium zinc oxide layer atop a gate dielectric layer; and contacting the amorphous indium gallium zinc oxide layer with silicon ions under conditions sufficient to reduce or eliminate the formation of oxygen vacancies.

In some embodiments, the present disclosure provides a method of passivating oxygen vacancy formation within amorphous indium gallium zinc oxide, including: forming a gate electrode atop a substrate; depositing a gate dielectric layer atop the gate electrode; depositing an amorphous indium gallium zinc oxide layer atop the gate dielectric layer; contacting the amorphous indium gallium zinc oxide layer with silicon ions; and depositing a conductive layer atop the amorphous indium gallium zinc oxide layer.

In some embodiments, the present disclosure relates to a thin film transistor including: an amorphous indium gallium zinc oxide layer atop a gate dielectric layer, wherein the amorphous indium gallium zinc oxide layer has a top portion, and bottom portion, wherein silicon ions are implanted within the top portion.

In some embodiments, a method for passivating oxygen vacancy formation within amorphous indium gallium zinc oxide, includes contacting an amorphous indium gallium zinc oxide layer with silicon ions under conditions sufficient to passivate the formation of a plurality of oxygen vacancies.

In some embodiments, the present disclosure relates to a non-transitory computer readable medium having instructions stored thereon that, when executed, cause a method for passivating oxygen vacancy formation within amorphous indium gallium zinc oxide, including: depositing an amorphous indium gallium zinc oxide layer atop a gate dielectric layer; and contacting the amorphous indium gallium zinc oxide layer with silicon ions under conditions sufficient to reduce or eliminate the formation of oxygen vacancies.

Other and further embodiments of the present disclosure are described below.

