Abstract: Corona charges are used to bias a wafer to push down mobile charges and then pull them up during temperature cycles. Mobile charge is measured from the drops in the corona voltage due to the mobile charges. Corrections are made in the measurements for dipole potentials, leakage and silicon band-bending.

Abstract: Corona charges are used to bias a wafer to push down mobile charges and then pull them up during temperature cycles. Mobile charge is measured from the drops in the corona voltage due to the mobile charges. Corrections are made in the measurements for dipole potentials, leakage and silicon band-bending.

Abstract: Corona charges are used to bias a wafer to push down mobile charges and then pull them up during temperature cycles. Mobile charge is measured from the drops in the corona voltage due to the mobile charges. Corrections are made in the measurements for dipole potentials, leakage and silicon band-bending.

Abstract: Corona charges are used to bias a wafer to push down mobile charges and then pull them up during temperature cycles. Mobile charge is measured from the drops in the corona voltage due to the mobile charges. Corrections are made in the measurements for dipole potentials, leakage and silicon band-bending.

Abstract: A method of measuring total charge of an insulating layer on a semiconductor substrate includes applying corona charges to the insulating layer, and measuring a surface photovoltage of the insulating layer after applying each of the corona charges. The charge density of each of the corona charges is measured with a coulombmeter. A total corona charge required to obtain a surface photovoltage of a predetermined fixed value is determined and used to calculate the total charge of the insulating layer. The fixed value corresponds to either a flatband or midband condition.

Abstract: A method of measuring total charge of an insulating layer on a semiconductor substrate includes applying corona charges to the insulating layer and measuring a surface photovoltage of the insulating layer after applying each of the corona charges. The charge density of each of the corona charges is measured with a coulombmeter. A total corona charge required to obtain a surface photovoltage of a predetermined fixed value is determined and used to calculate the total charge of the insulating layer. The fixed value corresponds to either a flatband or midband condition.

Abstract: A method of measuring total charge of an insulating layer on a semiconductor substrate includes applying corona charges to the insulating layer and measuring a surface photovoltage of the insulating layer after applying each of the corona charges. The charge density of each of the corona charges is measured with a coulombmeter. A total corona charge required to obtain a surface photovoltage of a predetermined fixed value is determined and used to calculate the total charge of the insulating layer. The fixed value corresponds to either a flatband or midband condition.

Abstract: A measurement of thickness of a metal oxide layer on a solder ball connection during semiconductor fabrication is demonstrated by an in-situ capacitance measurement of the oxide layer. A linear relationship is shown between the reactance of the metal oxide and its thickness. This linearity is derived empirically, and correlated to Auger Spectroscopy test results for accuracy. The linear relationship demonstrated with these measurements exhibits a linear correlation coefficient, R2, greater than or equal to 0.974. This close, linear relationship allows for accurate testing of the oxide thickness using standard electrical parameter measurements during wafer fabrication.

Abstract: A corona source is used to apply charge to an insulating layer. The resulting voltage over time is used to determine the current through the layer. The resulting data determines a current-voltage characteristic for the layer and may be used to determine the tunneling field for the layer.

Abstract: A method of measuring total charge of an insulating layer on a semiconductor substrate includes applying corona charges to the insulating layer and measuring a surface photovoltage of the insulating layer after applying each of the corona charges. The charge density of each of the corona charges is measured with a coulombmeter. A total corona charge required to obtain a surface photovoltage of a predetermined fixed value is determined and used to calculate the total charge of the insulating layer. The fixed value corresponds to either a flatband or midband condition.

Abstract: A needle is pressed into the backside oxide of a semiconductor wafer and a voltage applied to the wafer greater than the breakdown voltage of the oxide in order to make an electrical contact with the bulk material of the wafer. A capacitor plate is provided proximate to a wafer on a chuck and a Kelvin probe is provided proximate to the wafer. A varying voltage is applied between the chuck and the capacitor plate and a voltage is monitored between the Kelvin probe and the chuck. The monitored voltage remaining constant indicates electrical contact between the chuck and the wafer.

Abstract: Corona charge is applied to a semiconductor product wafer to reverse bias PN junctions. Measurements of voltage decay in the dark and in the light are made and combined to determine a PN junction leakage characteristic. A portion of the dark measurement is taken in the light to permit normalizing the light and dark measurements.

Abstract: A corona source is used to repetitively apply charge to an oxide layer on a semiconductor. A Kelvin probe is used to measure the resulting voltage across the layer. The tunneling field is determined based on the value of voltage at which the voltage measurement saturates.

Abstract: An apparatus for making and verifying electrical contact with the backside of a semiconductor wafer having a bulk portion covered with an insulating layer of oxide includes a contact probe, a wafer chuck having at least one probe vacuum groove and a probe aperture and a probe cylinder having a low pressure and a high pressure portion. The low pressure portion communicates with the probe vacuum groove and the probe aperture. The apparatus further includes a piston movably located between the low pressure and high pressure portions. The contact probe is attached to the piston and adapted to be protrudable from the probe aperture. The groove, aperture and low pressure portion are adapted to form a low pressure chamber with the wafer. The probe is urgeable to pierce the oxide and make electrical contact with the bulk portion of the wafer.

Abstract: A method for measuring junction leakage in a semiconductor product wafer while applying varying light to the wafer. A surface photovoltage characteristic for the wafer and an eddy current characteristic for the wafer in response to the light are measured. A junction leakage characteristic for at least one of junction types is determined by simultaneously measuring the surface photovoltage and the induced eddy current characteristics in response to a light flash.

Abstract: A conductive slit screen is placed between a corona gun and the surface of a semiconductor wafer. The charge deposited on the wafer by the gun is controlled by a potential applied to the screen. A chuck orients the wafer in close proximity to the screen. A desired charge is applied to the wafer by depositing alternating polarity corona charge until the potential of the wafer equals the potential of the screen.

Abstract: Corona charge is applied to an oxide layer on a semiconductor wafer. Then ultraviolet light is used to erase a grid pattern of the corona charge. Opposite polarity corona charge is then applied to the layer, resulting in a grid of field-induced PN junctions. The surface photovoltage of the junctions is measured over time to provide a measure of the mobile charge in the oxide layer.

Abstract: The surface of a wafer is charged with corona passing through a screen. The screen is part of a feedback loop that forces a constant corona current. This results in the potential of the wafer surface following the potential of the screen. This allows contemporaneous measurement of the surface charge and potential that are used to measure mobile charge in an oxide layer on the wafer.

Abstract: A conductive screen is placed between a corona gun and the surface of a semiconductor wafer. The charge deposited on the wafer by the gun is controlled by a potential applied to the screen. A chuck orients the wafer in close proximity to the screen. A desired charge is applied to the wafer by first applying a surplus of one charge to the wafer and then depositing an opposite polarity charge until the potential of the wafer equals the potential of the screen.