Operating a particle beam generator for a particle beam device

A computer program product including a program code which is loaded into a processor and which, when being executed, controls a particle beam device in such a way that a method of operating a particle beam generator for a particle beam device is carried out, the method comprising:

• providing a liquid metal from a container of a particle source of the particle beam generator to an emission device of the particle source, wherein the container comprises the liquid metal;
• carrying out a first heating cycle for cleaning the particle source, including:
• supplying a heating current to a heating device arranged at the emission device using a current supply unit,
• heating the emission device during a heating time period using the heating device heated by the heating current,
• measuring a value of a voltage drop at the heating device and/or at the current supply unit, and
• adjusting, using the current supply unit, and depending on the measured value of the voltage drop, at least one of:
• the heating current;
• and the heating time period;
• and
• carrying out a second heating cycle for cleaning the particle source and heating the emission device, using at least one of:
• the adjusted heating current;
• and the adjusted heating time period.

A particle beam device for imaging, analyzing and/or processing an object, comprising:

• at least one particle beam generator for generating a particle beam having charged particles, wherein the particle beam generator includes:
• a particle source having an emission device configured to emit charged particles and a container having liquid metal,
• a heating device arranged at the emission device,
• a current supply unit for providing a heating current, and
• a measuring unit for measuring a voltage drop at the heating device and/or at the current supply unit;
• and
• a processor into which a computer program product is loaded, wherein the computer program product comprises a program code which, when being executed, controls the particle beam device in such a way that a method of operating the particle beam generator of the particle beam device is carried out, the method including:
• (i) providing the liquid metal from the container of the particle source of the particle beam generator to the emission device of the particle source;
• (ii) carrying out a first heating cycle for cleaning the particle source, including:
• supplying the heating current to the heating device arranged at the emission device using the current supply unit,
• heating the emission device during a heating time period using the heating device heated by the heating current,
• measuring a value of a voltage drop at the heating device and/or at the current supply unit, and
• adjusting, using the current supply unit, and depending on the measured value of the voltage drop, at least one of:
• the heating current;
• and the heating time period;
• and
• (iii) carrying out a second heating cycle for cleaning the particle source and heating the emission device, using at least one of:
• the adjusted heating current;
• and the adjusted heating time period.

A method of operating a particle beam generator for a particle beam device, comprising:

• providing a liquid metal from a container of a particle source of the particle beam generator to an emission device of the particle source, wherein the container comprises the liquid metal;
• and
• cleaning the particle source during a heating cycle, including:
• supplying a heating current to a heating device arranged at the emission device using a current supply unit, and
• heating the emission device using the heating device heated by the heating current;
• measuring a value of a voltage drop at the heating device and/or at the current supply unit;
• determining a differential electrical power using the measured value of the voltage drop, wherein the differential electrical power is the difference between a first electrical power and a second electrical power;
• and
• stopping supplying the heating current if the differential electrical power exceeds a given target electrical power.