Apparatus and method for wafer pattern inspection

A semiconductor device inspection apparatus comprising:

• a sample stage that mounts a sample to be inspected;
• a first electron optical unit that directs electrons to a sample;
• a power source that connects the sample stage, said power source applying a potential to the sample stage so that the directed electrons are substantially reflected before the directed electrons reach a surface of the sample;
• a second electron optical unit that forms the reflected electrons into an image;
• an image detector that detects said image and converts the detected image into an electric signal;
• an image processor that inspects the sample based upon said electric signal from the image detector;
• and
• a pre-charge control unit that controls a charged state of the sample prior to the image being formed,
• wherein the formed image reflects a potential distortion between a normal portion and a faulty portion in the sample.

A semiconductor device inspection apparatus comprising;

• a electron optical system for illuminating an electron beam to a sample;
• a stage for mounting the sample;
• a device for giving a potential to reflect at least some of an illuminated electron beam without impinging the sample;
• an image detection unit for detecting the reflected electron beam;
• an image processing unit for analyzing an image obtained in the image detection unit and inspecting the sample;
• and
• a pre-charge control system for controlling a charged state of the sample prior to the image being formed,
• wherein the pre-charge control system includes a second electron gun and a grid arranged between the second electron-gun and the sample, and
• wherein the formed image reflects a potential distortion between a normal portion in the sample and a faulty portion in the sample.

A semiconductor device inspection apparatus comprising;

• means for illuminating an electron beam to a sample;
• means for generating an electric field at the sample;
• means for detecting said illuminated electron which reflected a form and a potential distribution in a surface of the sample without impinging the sample and for forming a image based on the illuminated electron;
• means for analyzing the image and inspecting the sample;
• and
• means for charging the sample and controlling a charged state of the sample prior to the image being formed,
• wherein said charged state of the sample is controlled to reflect a potential distortion between a potential at a normal portion in the sample and a potential at a faulty portion in the sample.