Inline method to monitor ONO stack quality

A method comprising:

• forming on a substrate a test structure including a tunneling-layer comprising a nitrided oxide and a charge-storage-layer overlying the tunneling-layer, the charge-storage-layer comprising a first charge-storage layer adjacent to the tunneling-layer, and a second charge-storage layer overlying the first charge-storage layer, wherein the first charge-storage layer is separated from the second charge-storage layer by a thin anti-tunneling layer comprising an oxide;
• depositing a positive charge on the uppermost surface of the charge-storage-layer and determining a positive tunneling voltage for the structure;
• depositing a negative charge on the uppermost surface of the charge-storage-layer and determining a negative tunneling voltage for the structure;
• determining a differential tunneling voltage by calculating a difference between the positive and negative tunneling voltages,
• wherein forming the structure comprises removing a blocking-dielectric-layer comprising a high K dielectric overlying the charge-storage-layer.

A method comprising:

• forming on a substrate a test structure including a tunneling-layer comprising a nitrided oxide and a charge-storage-layer overlying the tunneling-layer, the charge-storage-layer comprising a first charge-storage layer adjacent to the tunneling-layer, and a second charge-storage layer overlying the first charge-storage layer, wherein the first charge-storage layer is separated from the second charge-storage layer by a thin anti-tunneling layer comprising an oxide;
• depositing a positive charge on the uppermost surface of the charge-storage-layer and determining a positive tunneling voltage for the structure;
• depositing a negative charge on the uppermost surface of the charge-storage-layer and determining a negative tunneling voltage for the structure;
• determining a differential tunneling voltage by calculating a difference between the positive and negative tunneling voltages;
• and
• determining from the differential tunneling voltage an operating characteristic of a non-volatile memory non-volatile memory transistor comprising a charge-storage-layer and a tunneling-layer fabricated concurrently with the charge-storage-layer and tunneling-layer of the structure,
• wherein forming the structure comprises forming the structure on a monitor substrate processed concurrently with a product substrate on which the non-volatile memory transistor is fabricated.

A method comprising:

• forming on a substrate a test structure including a tunneling-layer comprising a nitrided oxide and a charge-storage-layer overlying the tunneling-layer, the charge-storage-layer comprising a first charge-storage layer adjacent to the tunneling-layer, and a second charge- storage layer overlying the first charge-storage layer, wherein the first charge-storage layer is separated from the second charge-storage layer by a thin anti-tunneling layer comprising an oxide;
• depositing a positive charge on the uppermost surface of the charge-storage-layer and determining a positive tunneling voltage for the structure;
• depositing a negative charge on the uppermost surface of the charge-storage-layer and determining a negative tunneling voltage for the structure;
• determining a differential tunneling voltage by calculating a difference between the positive and negative tunneling voltage;
• and
• determining from the differential tunneling voltage an operating characteristic of a non-volatile memory transistor comprising a charge-storage-layer and a tunneling-layer fabricated concurrently with the charge-storage-layer and tunneling-layer of the structure;
• and
• halting fabrication of non-volatile memory transistors formed concurrently with the structure when the differential tunneling voltage is outside a specified range of voltages.

A method comprising:

• forming a structure including a charge-storage-layer overlying a tunneling-layer on a substrate;
• depositing a positive charge at a first site on the uppermost surface of the charge-storage-layer and determining a first voltage to establish a first leakage current through the charge-storage-layer and the tunneling-layer;
• depositing a negative charge at a second site on the uppermost surface of the charge-storage-layer and determining a second voltage to establish a second leakage current through the charge-storage-layer and the tunneling-layer;
• and
• determining a differential voltage by calculating a difference between the first and second voltages,
• wherein forming the structure comprises removing a blocking-dielectric-layer comprising a high K dielectric overlying the charge-storage-layer.