Experimental Research Of Indentation Testing Of GaAs Material

With the development of communication technology,semiconductor materials are widely used in military,communications,medical and other aspects.Compared with traditional silicon semiconductor materials,gallium arsenide has the advantages of wide band gap,high electron mobility,good photoelectric characteristics,radiation resistance and high frequency performance.It is the most widely used and most mature research after silicon materials.One of the compound semiconductor materials.On the one hand,gallium arsenide material is a typical brittle material,which is easily damaged during the processing of materials and products.On the other hand,the typical service conditions of gallium arsenide materials are complex environments with force and electric coupling.It is especially important to study the deformation damage law of GaAs materials during mechanical processing and the evolution of micro-mechanical properties of materials under the coupling of force and electric.In this paper,micro-nano indentation testing technology was used to test the micro-mechanical properties of gallium arsenide materials.By summarizing and analyzing the indentation test research of GaAs materials at home and abroad and the recent progress of the research on the force and electric coupling test of semiconductor materials,the research background of this paper and the study of the micro-deformation damage and force-electric coupling test of gallium arsenide indentation are described.Significant significance;based on the micro-nano indentation test platform independently developed by the laboratory,the construction of the nanoindentation test system and the functions of each unit are introduced,especially the connection of the external electric field equipment and the treatment method of the test piece insulation in the electro-mechanical coupling test.A force-electric coupling indentation test system was established.Based on the basic theory of indentation test — Oliver-Pharr method and force-electric coupling and decoupling theory,the theoretical basis for studying the micro-mechanical properties of gallium arsenide materials under different conditions was established.Based on the above basics,the authors conducted a series of room temperature indentation test tests on undoped gallium arsenide materials using diamond glassindenters and diamond flat heads under normal temperature conditions.According to the test results,we draw the following conclusions: 1 As the test press-in load increases,the hardness of the gallium arsenide material decreases and the elastic modulus decreases;2 by observing the residual indentation morphology,we obtain the glass pressure The crack pattern under the head is triangular prism type,the minimum force value for crack generation is between 100~120mN,the crack pattern under the flat pressure head is flat cylindrical shape,and the minimum force value for crack generation is 150 mN,and with the indentation load Increase,the crack length under both indenters increases;3 by comparing the deformation of the material under the glass indenter and the indenter(round head of the indenter,diameter 2um),we believe that under the same force value(two The geometry of the indenter is equivalent.The flat head has a deeper depth on the surface of the gallium arsenide material than the glass indenter,and the indentation shape has a longer crack length,and the damage to the surface of the material is more serious,so the material is involved.For the selection of the machining tool,the sharper cutting tool should be preferred.In addition,we also conducted a force-electric coupling nanoindentation test for GaAs materials.According to the test results,the following conclusions are drawn: 1 Under the condition that the applied electric field voltage is constant,the resistance of the material to be tested becomes smaller as the indentation load increases;2 under the condition that the indentation load is constant,different additions are applied.The electric field voltage,the mechanical properties of the gallium arsenide material did not change,that is,the applied electric field did not affect the mechanical properties of the material;3 under the condition of constant applied electric field voltage,the cyclic indentation loading test was applied to the gallium arsenide material.The current measurement signal can be enhanced with the increase of the indentation depth,which proves that the current signal can be used to monitor the indentation depth,which provides a reference for the application of gallium arsenide materials in complex environments.