Method and apparatus for simulating a surface photo-voltage in a substrate
AssigneeQC Solutions, Inc.
InventorsEmil Kamieniecki, Krzysztof E. Kamieniecki, Jeffrey L. Sauer, Janusz Butkiewicz
Life of this patent
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Abstract
This invention relates to a method and apparatus for simulating a surface photo-voltage, more particularly with a photodiode on a process sized disk for calibrating surface photo-voltage measurement devices. The device for simulating a surface photo-voltage includes the photodiode, the disk, a resistor, and may further include an operational amplifier. The apparatus for simulating a surface photo-voltage of the current invention facilitates calibration of surface photo-voltage measurement devices by using a process sized disk to fit directly on a surface photo-voltage measurement chuck.
Claims27
An apparatus for simulating a surface photo-voltage in a semiconductor wafer, the apparatus comprising:
- a) a photodiode comprising an anode and a cathode;
- b) a resistor comprising a first terminal and a second terminal, wherein the resistor first terminal is in electrical communication with one of the photodiode anode and cathode;
- and
- c) a disk comprising a first surface and a second surface, wherein the resistor second terminal and the other of photodiode anode and cathode are in electrical communication with the disk first surface.
An apparatus for measuring a simulated surface photo-voltage, the apparatus comprising:
- a) a simulator disk comprising:
- i) photodiode comprising an anode and a cathode;
- ii) a resistor comprising a resistor first terminal and a resistor second terminal, wherein the resistor first terminal is in electrical communication with one of the photodiode anode and cathode;
- and
- iii) a disk comprising a first surface and a second surface;
- wherein the resistor second terminal and the other of photodiode anode and cathode are in electrical communication with the disk first surface;
- b) a measurement chuck comprising a first surface, wherein the measurement chuck first surface is in electrical communication with the disk second surface;
- c) a light source;
- and
- d) a surface photo-voltage measurement probe positioned adjacent to the photodiode anode.
A method for simulating a surface photo-voltage in a semiconductor wafer, the method comprising the steps of:
- a) providing an apparatus for generating a simulated surface photo-voltage, the apparatus comprising:
- i) a simulator disk comprising:
- (1) a photodiode comprising an anode and a cathode;
- (2) a resistor comprising a first terminal and a second terminal, wherein the resistor first terminal is in electrical communication with the photodiode anode;
- (3) a disk comprising a first surface and a second surface;
- wherein the resistor second terminal and the photodiode cathode are in electrical communication with the disk first surface;
- and
- ii) a light source;
- b) generating a light from the light source;
- c) illuminating the simulator disk with the light from the light source;
- and
- d) generating a signal in response to the light from the light source in the simulator disk.
An apparatus for simulating a surface photo-voltage in a semiconductor wafer, the apparatus comprising:
- a) a photodiode comprising an anode metalization and a cathode metalization;
- b) a disk having a trench therein, wherein the disk is attached to the photodiode with an optical epoxy;
- c) a resistor comprising two terminals wherein, the resistor first terminal is attached to the trench and the photodiode cathode metalization with a first volume of conductive epoxy, and the resistor second terminal is attached to the photodiode anode metalization with a second volume of conductive epoxy.
An apparatus for simulating a surface photo-voltage in a semiconductor wafer, the apparatus comprising:
- a) a photodiode comprising an anode and a cathode;
- b) a resistor comprising a first terminal and a second terminal, wherein the resistor first terminal is in electrical communication with one of the photodiode anode and cathode;
- c) an operational amplifier comprising an operational amplifier first input terminal, an operational amplifier second input terminal and an operational amplifier output terminal, wherein the operational amplifier first input terminal is in electrical communication with one of the photodiode anode and cathode, the operational amplifier second input terminal is in electrical communication with the other of the photodiode anode or cathode and the resistor first terminal, and the operational amplifier output terminal is in electrical communication with the resistor second terminal;
- and
- d) a disk comprising a first surface, wherein the photodiode is mounted on the disk but not in electrical communication with the disk.
Dependencies are inferred from the claim text.