The technical difficulties of semiconductor chips mainly include the following aspects:

1. Advanced processing technology: Semiconductor chip manufacturing needs advanced technical support, and its complexity is difficult to describe in words. A Z-basic MOSFET structure contains many complicated steps and needs precise control and operation. Therefore, how to ensure the quality and reliability of the chip has become an important challenge.

2. Material selection and optimization: The key to semiconductor chip material selection lies in the optimization and innovation of material performance. For example, silicon is a commonly used semiconductor material in Z at present, but with the development of technology, other materials such as silicon carbide and gallium nitride are also widely used. How to select and optimize materials to meet the performance and reliability requirements of chips is an important technical difficulty.

3. Miniaturization technology: With the continuous improvement of chip performance, the size of the chip is also shrinking. It is an important technical difficulty to realize the miniaturization of the chip on the premise of ensuring the performance of the chip. This requires in-depth research and optimization of the chip structure, materials and technology.

4. Packaging technology: The packaging technology of semiconductor chips is an important link to ensure chip performance and reliability. Packaging technologies include wire bonding, flip chip, wafer-level packaging and through silicon vias (TSV), etc. The selection and optimization of these technologies need to be based on the performance of the chip and application scenarios.

5. Testing and verification technology: The testing and verification technology of semiconductor chips is an important means to ensure the quality and reliability of chips. Testing and verification technologies include temperature cycling, high-temperature working life, temperature and humidity bias, autoclave/unbiased HAST, high-temperature storage, electrostatic discharge, etc. These tests can help to find out potential failure mechanisms and improve the reliability of

6. Reliability and life: The reliability and life of semiconductor chips are important indicators of chip performance. How to improve the reliability and life of the chip is an important technical difficulty. This requires in-depth research and optimization of the structure, materials and technology of the chip, as well as strict control and management of the use environment and mode of the chip.

7. Cost control: The cost of semiconductor chips is an important factor affecting the competitiveness of the chip market. How to reduce the cost of the chip while ensuring the performance and reliability of the chip is an important technical difficulty. This requires in-depth research and optimization of chip production technology, material selection and equipment procurement.

   To sum up, the technical difficulties of semiconductor chips mainly include            advanced processing technology, material selection and optimization,     miniaturization technology, packaging technology, testing and verification technology, reliability and life, and cost control. The solution of these technical difficulties requires continuous innovation and research, as well as the joint efforts of the government, enterprises and scientific research institutions.