Description: Sichuan Huacan Electronics co., LTD as the project undertaking unit, and Institute of Microelectronics, Chinese Academy of Sciences as the cooperative unit of sichuan Province's 2019 key science and Technology plan project: the key design technology research of new Dual-magnetic Hall integrated circuit participated in the final defense and completed the project acceptance this month.

Project name: Research on key design technology of new Double-pole Hall integrated circuit

Project approval fund: 400,000 yuan

Finance Bureau grant: $200,000

Achievements: Obtained 3 patents and published 2 international academic papers. Passed the conclusion reply of the expert group, complete acceptance.

This project research based on the double magnetic magnitude response hall device product development demand, research and analysis the double magnetic hall device structure, work mechanism, internal response to the changes in physical properties, solve the analysis of the common problems of hall sensor product design and development, which reveal the device structure design differences, understand the effect of the magnetic response, circuit topology operation characteristics bring the function of the difference, Provide guiding design principles for product design. Research based on the electromagnetic physical field theory and mechanism analysis, using 3 d modeling and simulation technology, mixed-signal circuit simulation technology, respectively on hole structure modeling, simulation precision design of device structure, fitting, to master the key technology, high precision hole piece voltage response design high performance hall sensor circuit is the key technical difficulties, including research bistable trigger circuit, Voltage regulator, internal junction capacitance, device structure characteristics and other aspects.

Through the accumulation of the project research work and help to promote domestic high-end hall sensor IC independent development and innovation ability, break the field of integrated circuit sensor circuit core key technology for long-term foreign technology monopoly, imports the adverse situation, to achieve a breakthrough of the localization of products, gradually replaced with foreign products, lay a solid technical foundation accumulation, And bring good economic returns and social benefits.

1) Main research contents

During the development of the project, the research content required for product development includes:

A. 3d simulation modeling and internal carrier distribution extraction of hall plate structure in Hall sensor.

Hall sensor circuit based on magnetic field response trigger, hall plate (disk) integrated with matching process specifications and chip size structure is the key to design, since the magnetic characteristic response of hall voltage is required to achieve stable and high response amplitude, while reducing the chip size as much as possible, so the design must compromise. The thickness and doping concentration of Hall sheet matching the actual process are selected to ensure sufficient response characteristics.

Research combined with the actual process parameters, refer to the actual device size, finished the 3 d simulation, the hall plate structure respectively simulated optimization, size, thickness and doping concentration study designed A, B two hall design scheme, and doping concentration extraction parameters are fitted to the sample, and through comparative analysis, understand the response mechanism, Theoretically, the regulation mechanism of response carriers is mastered, and the modulation and optimization design objectives of Hall voltage response characteristics are realized, so as to master the key technology and method of hall plate structure design of multi-process platform.

B. Key circuit structure technology of Hall voltage regulator

The analysis and optimization of the voltage regulator circuit is completed. Theoretical research shows that in the actual hall device manufacturing process, due to the particle charge induction effect introduced by the impurities in the process line, the piezoelectric effect of the device package and the influence of environmental temperature changes, the core voltage regulator will be misadjusted, resulting in the normal operation of the device. Therefore, the necessary optimization technology of Hall imbalance voltage regulator is studied to avoid the influence of voltage imbalance. The imbalance mechanism is carefully studied and analyzed, and the effective circuit structure transformation is adopted to realize the temperature drift of the voltage regulator with a small temperature, to suppress the imbalance voltage to the maximum extent, and to realize the normal working response. Master the key design techniques of circuit optimization to suppress offset voltage, and realize the optimization of device performance.

C. New double pole response circuit design technology

Based on the design requirements of dual-pole induction Hall integrated circuit sensor chip, the dual-pole induction Hall integrated circuit sensor response technology is mastered by constructing and adjusting the circuit topology and designing the bistable compensation circuit to realize the dual-pole response design structure. The research can realize the product design based on the application needs different north and south magnetic pole response function. Provide technical accumulation for follow-up research.

D. Capacitance structure and voltage jitter optimization of Hall sensor circuit.

When the chip works at a higher temperature, the mobility of the semiconductor material itself changes with the temperature, which will further affect the Hall voltage drift and the working point of the analog component changes, resulting in the drift and misjudgment of the output signal, affecting the normal operation of the electronic system. Through comprehensive evaluation and analysis of circuit structure, modulation optimization of key junction capacitance and operating point that affect voltage jitter is carried out to suppress the maladjustment of operating point with temperature change. Simulation and test analysis results verify the optimization technology of voltage jitter, and realize the optimization and adjustment of voltage regulator source of the device.

E. Hall sensor magnetic field analysis and testing technology.

In order to effectively analyze the functional characteristics of the product, it is necessary to analyze and test the switching magnetic field signal to accurately grasp the characteristics of the device. During the project, a magnetic field analysis and testing platform was developed. Through theoretical investigation, selection of magnetic materials and practical verification experiments, hall sensor test and analysis system suitable for project research is designed to meet the verification and analysis requirements of typical products and series of products of the project.

2) Technical key

Based on the development of application requirements, this project studies and solves the key technical problems of core chip design of dual-magnetic induction Hall sensor. Mainly completed the hall three-dimensional simulation modeling analysis, key circuit topological structure analysis and design, including the voltage source, stable capacitance, flip-flop circuit device, and other core technology key problems, research accumulated related technology base, key problems for hall sensor circuit device technical solutions to provide practical strategies.

3) Technical route

This project uses the hall sensor development experience and technology of Institute of Microelectronics, Chinese Academy of Sciences for reference. According to the circuit functional structure requirements of the target product, the overall parameters of the device are regulated and designed, and the technical route is mature and controllable. Relevant experiences in the early stage of the institute of microelectronics research technique has been successfully used much money hall sensor design, development, and by the sichuan HuaCan electronics company assist with analysis, testing and packaging production capacity experiment, related technical route to accumulate hall-effect sensor chip design can help the core technology breakthrough, and complete product development target, main follow technical route:

A. Hall disk structure simulation design and analysis technology.

Based on previous study of products, and master the way of simulation hall plate structure is built and parameter adjustment method, to combine different process platform manufacturing requirements, to carry out the hall plate carrier response of the structure of control technology, accurate and detailed evaluation bias magnetic field affects the mobile carrier mechanism and process, using the simulation output and fitting test and analysis results, The structural parameters of hall disk are adjusted comprehensively, and the expected design goal is achieved by comparing the carrier parameters extracted from the study with the measured results.

B. Hall sensor circuit development technology based on bipolar process.

Developing based on bipolar technology hall sensor, research completed including voltage source module, trigger response module, capacitance stability module analog circuit working point set the theoretical basis of research, using the simulation software, circuit structure to carry out detailed analysis of the development of typical products, matching point are set for the appropriate circuit, circuit so as to realize the expected function.

C. Hall sensor static magnetic field testing and analysis technology.

Drawing on the test and analysis technology of the developed series of products, complete the test, analysis and verification of wafer, wafer level and packaged products. Based on the current rich test and analysis capabilities, develop supporting test devices to meet the test application requirements of the double-pole magnetic field of the project products.

4) Innovation

This project focuses on the key design technology of new high-performance Hall sensor. Based on theoretical mechanism analysis, the key technology of hall plate parameter modulation is studied by 3d simulation, and the design technology innovation of high-precision Hall plate voltage signal response is realized. At the same time, based on the application requirements, the product solves the common key technical problems in product design, including hall carrier regulation design technology, voltage regulator signal temperature drift modulation technology, junction capacitor voltage stability control, bistable trigger design and other core technologies, and develops a new north-south double magnetic pole double response Hall sensor. This new product breaks the limitation of the traditional sensor monopole magnetic field (S pole) response and is based on the innovative research of market application demand. The accumulation of necessary research work in this area is an urgent need to realize the self-innovation of Hall sensor products.