Technology Design Of Low Voltage & Low Leakage Transient Voltage Suppressor

Transient Voltage Suppressor（TVS）is a new schottky rectifier,is a diode form of high efficient protective device,which can effectively protect the precision components of the electronic circuit from the damage of various surge pulses.It is widely used in household appliances,electronic instruments,precision equipment,computer and communication equipment.In practice,TVS usually has three production techniques.that is:n-type substrate n-type epitaxial,doped with boron,formed from p-type epitaxial substrate p-type doped phosphorus p-n junction TVS diode;The n-p junction TVSdiode wasformed By using N-type substrate;The n-p junction TVS diode was formed By using p-type substrate;These processes can meet the design parameters requirements when making more 7V products,and its characteristic curve is hard breakdown,leakage current is small.The product curve below 7V becomes soft breakdown and the leakage current increases.Usually the leakage current of 5V/1W products is around 200μA.This design intends to reduce the leakage below to 0.5μA and lower the leakage current through proper process design,improve its characteristic curve to hard puncture,and reduce the power of the product.The main work of this thesis is summarized as follows:（1）RTP,Rapid annealing of aluminum process.The design selects N substrate and the crystal is 100,This material plays a role in aluminum shrinkage during the rapid annealing of aluminum metal,Solve the problem of aluminum diffusion,Adjust annealing temperature and annealing time,The breakdown voltage of the rapid annealing of aluminum is reduced from10V to 5⁷V.（2）Test the parameters of batch flow products,the relative test of the products made by the convection plate was carried out.So the variation curves of various electrical parameters and at least 6 sets of test data were obtained and analyzed.The test results show that the V_BR、I_R、and V_C of the TVS products can meet the design requirements.（3）Process repeatability and operable verification.In order to ensure design scheme is feasible and has the process repeatability and maneuverability.The design also carried out a variety of reliability experiments on the product.The reliability test and antistatic test of high temperature anti-deviation were carried out.The experimental results show that the test data conforms to the normal distribution and can meet the design requirements.Finally,the designed product of low voltage low leakage 5V TVS were through different stages of electrical and reliability tests.The electrical parameters and reliability of the product can meet the design requirements and the important indicator of leakage current is reduced to less than 0.5μA.