Backside nitride removal to reduce streak defects
AssigneeTexas Instruments Incorporated
InventorScott Cuong Nguyen
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Abstract
Exemplary embodiments provide a method for fabricating an integrated circuit (IC) device with reduced streak defects. In one embodiment, the IC device structure can be formed having a first pad oxide-based layer on a front side of a semiconductor substrate and having an oxide-nitride-based structure on a backside of the semiconductor substrate. The IC device structure can be etched to remove a nitride-related material from the backside oxide-nitride-based structure, and further to remove the first pad oxide-based layer from the front side of the semiconductor substrate. On the removed front side of the semiconductor substrate a second pad oxide-based layer can be formed, e.g., for forming an isolation structure for device component or circuitry isolation.
Claims19
A method for fabricating an integrated circuit (IC) device comprising:
- forming a first pad oxide layer on a front side of a semiconductor substrate;
- partially etching the first pad oxide layer using a composition containing hydrofluoric acid;
- following the partial etching, etching the backside of the semiconductor substrate to remove a nitride therefrom;
- following the backside etching, removing the partially etched first pad oxide layer from the front side of the semiconductor substrate using a composition containing hydrofluoric acid;
- and
- after removing the partially etched first pad oxide layer, forming a second pad oxide-layer on the front side of the semiconductor substrate for forming an isolation structure for an IC device.
A method for fabricating an integrated circuit (IC) device, comprising:
- forming a first pad oxide-based layer on a front side of a semiconductor substrate and forming an oxide-nitride-based structure on a backside of the semiconductor substrate;
- partially etching the first pad oxide-based layer using a composition containing hydrofluoric acid for about 600 seconds;
- etching the backside oxide-nitride-based structure to remove a nitride-related material therefrom using a composition containing phosphoric acid for about 3100 seconds or longer;
- removing the partially etched first pad oxide-based layer using a composition containing hydrofluoric acid for about 300 seconds;
- megasonically cleaning the etched IC device using a composition containing ammonium hydroxide and hydrogen peroxide for about 600 seconds;
- and
- after removing the partially etched first pad oxide-based layer, forming a second pad oxide-based layer on the front side of the semiconductor substrate for forming an isolation structure for an IC device.
Dependencies are inferred from the claim text.