Magnification and rotation calibration patterns for particle beam projection system

A method of calibrating a projection electron beam lithography system, comprising the steps of:

• providing a magnification reticle pattern and a magnification target pattern,
• providing an image of a rotation reticle pattern and a rotation target pattern,
• producing an electron beam,
• directing the electron beam through said magnification reticle pattern and onto said magnification target pattern,
• scanning said image of said magnification reticle pattern across said magnification target elements with a calibrated deflection,
• determining the distance between peaks of target patterns as indicated by secondary electrons or electrons backscattered from said magnification target pattern,
• calculating the deviation from a standard for said distance between peaks of target patterns from said magnification target pattern and calculating the magnification deviation,
• directing the electron beam through the rotation reticle pattern and onto the rotation target pattern,
• determining the distance between peaks of target patterns as indicated by secondary electrons or electrons backscattered from said rotation target pattern, and
• calculating the deviation from a standard for said distance between peaks of said rotation target pattern and calculating the rotation deviation with respect to rotational orientation.

A projection particle beam lithography system with means for calibration thereof comprising:

• a magnification reticle pattern of magnification features and a magnification target pattern of magnification target elements,
• a rotation reticle pattern of rotation pattern features and a rotation target pattern of target elements,
• a particle beam,
• projection means for directing the particle beam through said magnification reticle pattern and onto said magnification target pattern,
• scanning means for scanning an image of said magnification reticle pattern across said magnification target elements with a calibrated deflection,
• first measurement means for determining the distance between peaks of target patterns as indicated by particles backscattered from said magnification target pattern,
• first calculation means for calculating the deviation from a standard for said distance between peaks of target patterns from said magnification target pattern and calculating the magnification deviation,
• guidance means for directing the particle beam through the rotation reticle pattern and onto the rotation target pattern,
• second measurement means for determining the distance between peaks of target patterns as indicated by particles backscattered from said rotation target pattern, and
• second calculation means for calculating the deviation from a standard for said distance between peaks of said rotation target pattern and calculating the rotation deviation with respect to rotational orientation.

A projection electron beam lithography system, comprising:

• first pattern means for providing a magnification reticle pattern and a magnification target pattern,
• second pattern means for providing a rotation reticle pattern and a rotation target pattern,
• beam means for producing an electron beam,
• first directing means for directing said electron beam through said magnification reticle pattern and onto said magnification target pattern,
• scanning means for scanning an image of said magnification reticle pattern across said magnification target elements with a calibrated deflection,
• first measuring means for determining the distance between peaks of target patterns as indicated by secondary electrons or electrons backscattered from said magnification target pattern,
• first calculating means for calculating the deviation from a standard for said distance between peaks of target patterns from said magnification target pattern and calculating the magnification deviation,
• second directing means for directing the electron beam through the rotation reticle pattern and onto the rotation target pattern,
• second measuring means for determining the distance between peaks of target patterns as indicated by secondary electrons or electrons backscattered from said rotation target pattern, and
• second calculating means for calculating the deviation from a standard for said distance between peaks of said rotation target pattern and calculating the rotation deviation with respect to rotational orientation.

A semiconductor device fabrication method comprising characterized by the steps comprising:

• performing wafer fabrication;
• performing mask fabrication;
• performing wafer processing;
• performing assembly and inspection;
• said method employing a charged particle projection particle beam lithography system steps calibrated by providing an image of a magnification reticle pattern of magnification features and a magnification target pattern of magnification target elements;
• providing a rotation reticle pattern of rotation pattern features and a rotation target pattern of target elements;
• producing a particle beam and directing said particle beam through said magnification reticle pattern and onto said magnification target pattern;
• scanning said image of said magnification reticle pattern across said magnification target elements with a calibrated deflection;
• determining the distance between peaks of target patterns as indicated by particles backscattered from said magnification target pattern;
• calculating the deviation from a standard for said distance between peaks of target patterns from said magnification target pattern and calculating magnification deviation;
• directing the particle beam through the rotation reticle pattern and onto the rotation target pattern;
• scanning the image of said rotation reticle pattern across said rotation target elements with a calibrated deflection;
• determining the distance between peaks of target patterns as indicated by particles backscattered from said rotation target pattern;
• calculating the deviation from a standard for said distance between peaks of said rotation target pattern and calculating rotation deviation;
• and
• then completing the formation of said semiconductor device with said calibrated particle beam lithography system.