PCB ion trap mass analyzer adopts linear ion trap structure, its electrode is processed by PCB, and its cross section is designed to be rectangular. The reasons for adopting this design are as follows: first, linear ion trap has higher ion storage capacity and ion capture efficiency than traditional three-dimensional trap, so it has higher sensitivity in analysis and detection; Second, rectangle is one of the simplest geometric structures, which is very convenient for machining and assembly. Third, PCB price is low, processing technology and method mature.

The PCB ion trap consists of two pairs of PCB electrodes and a pair of metal end cap electrodes. All PCB electrodes are 2.2 mm thick and 46mm long. The surface of each PCB electrode is machined into three parts: a 40mm middle electrode and two 2.7mm end electrodes. A 0.3mm wide insulating tape is machined between the middle electrode and the two end electrodes so that different operating voltages can be loaded on the middle electrode and the two end electrodes respectively. Four positioning holes with a diameter of 1mm are processed on the electrodes at both ends for ion trap assembly. The end cover electrode is made of stainless steel with a thickness of 0.5 mm and processed into a special shape, so it can be closely matched with the positioning holes at both ends of the PCB electrode to form a PCB ion trap.

When the ion trap mass analyzer works, radiofrequency voltage is applied to the middle electrode of the PCB to form a radial AC bound electric field, while dc voltage is applied to the two end electrodes to form an axial DC bound electric field. A hole with a diameter of 3mm is processed in the center of each end cap electrode. Ions generated by external ion sources can enter the ion trap through the hole on the end cap electrode, and are bound and stored in the ion trap under the joint action of radial AC bound electric field and axial DC bound electric field. One of the two pairs of PCB electrodes is centrally machined with a 0.8 mm wide slit as an ion extraction channel, which is used to selectively discharge the ions stored in the ion trap out of the trap for detection and quality analysis.