Lucent Technologies Inc.

Agere Systems Inc.

Agere Systems Guardian Corp.

Carlos M Chacon

Pradip Kumar Roy

Sundar Srinivasan Chetlur

Sailesh Chittipeddi

David Charles Brady

Minesh Amrat Patel

Brian E Harding

A non-contact method for determining a quality of a semiconductor dielectric. The method includes depositing a charge on a dielectric to achieve a high voltage on the dielectric, measuring a voltage drop of the dielectric as a function of time, and determining a soft breakdown voltage of the dielectric from the voltage drop as a function of time. The amount of charge that is deposited may vary. For example, the charge may be deposited until a voltage that ranges from about 4 megavolts to about 16 megavolts is achieved on the dielectric. The amount of charge may also depend on the thickness of the dielectric. For example, applying a charge as a function of the thickness may include applying 4 megavolts when the thickness is about 1.2 nm or applying 16 megavolts when the thickness is about 5.0 nm.

Non-contact method for determining quality of semiconductor dielectrics

A transistor gate dielectric structure includes an oxide layer formed on a substrate, a superjacent nitride layer and a transition layer interposed therebetween. The presence of the transition layer alleviates stress between the nitride and oxide layers and minimizes any charge trapping sites between the nitride and oxide layers. The transition layer includes both nitrogen and oxygen as components. The method for forming the structure includes forming the transition layer using a remote nitridation reactor at a sufficiently low temperature such that virtually no nitrogen reaches the interface formed between the oxide layer and the substrate. The oxide layer/substrate interface is relatively pristine and defect-free. In an exemplary embodiment, the oxide layer may be a graded structure formed using two distinct processing operations, a first operation at a relatively low temperature and a final operation at a temperature above the viscoelastic temperature of the oxide film.

Method and structure for oxide/silicon nitride interface substructure improvements

The present invention provides a method of determining a trap density of a semiconductor substrate/dielectric interface. In one embodiment, the method comprises measuring a current within a semiconductor substrate resulting from a flow of carriers from traps located near the interface, wherein the measured current is a function of the number of traps located at the interface, and determining the trap density as a function of the measured current.

Method of determining a trap density of a semiconductor/oxide interface by a contactless charge technique

A method and apparatus for in-line, non-contact depletion capacitance measurement of a semiconductor wafer using non-contact voltage measurement and non-contact surface photovoltage response.

In-line non-contact depletion capacitance measurement method and apparatus

The present invention provides a non-contact method for determining whether a contaminant is present in a semiconductor wafer having a substrate/dielectric interface formed thereon. in one advantageous embodiment, the method comprises field inducing a junction in equilibrium inversion in the semiconductor wafer device. A conventional corona source may be used to induce the junction to equilibrium inversion. This particular embodiment further includes forming a contaminant junction near the substrate/dielectric interface when the contaminant is present in the semiconductor wafer by adding charge and pulsing the junction out of equilibrium. A surface voltage measurement, which may be taken with a Kelvin probe, is obtained by measuring a change in a surface voltage as a function of time. The method further includes determining whether the contaminant is present in the semiconductor wafer from the change in the surface voltage. When the contaminant is present in the device, the change in the surface voltage is negligible. This negligible change is in stark contrast to the change in surface voltage that occurs in a non-contaminated device. The data obtained from these surface voltages can be plotted with conventional devices to yield the change in surface voltage with respect to time.

Non-contact method for determining the presence of a contaminant in a semiconductor device

The present invention provides a method for controlling a process parameter for fabricating a semiconductor wafer. In one embodiment, the method includes forming a test substrate using a given process parameter, determining a flatband voltage of the test substrate, and modifying the given process parameter to cause the flatband voltage to approach zero. The process parameter that is modified to cause the flatband voltage to approach zero may vary. The flatband may be determined by a non-contact method, which uses a kelvin probe to measure the flatband voltage and a corona source to deposit a charge on the test substrate.

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Orlando, FL, United States of America

Carlos M Chacon