QFP/quartz Adhesive Bonding with Surface Treatment for Physical Security of Edge Artificial Intelligence Devices

We studied a method of quad flat package (QFP)/quartz adhesive bonding. This bonding technology is required for developing physical security of edge artificial intelligence (AI) devices using a nanoartifact metrics (NAM) chip. Relationships between contact angle and bonding strength of QFP/adhesive or quartz/adhesive were investigated under several surface treatment methods including vacuum ultraviolet (VUV) treatments, and plasma treatments. VUV irradiation in the presence of nitrogen gas (VUV/N2) treatment reduced the contact angle of the QFP and quartz surface from 99.2° to 5.0°, which improved QFP/adhesive bonding strength 5.7 times. Furthermore, the bonding strength of QFP/adhesive/quartz bonding with the VUV/N2 treatment shows a shear strength of 14.2 MPa. It is 2.4 times higher value than that without the treatment. These results are a promising step for highly reliable QFP/quartz bonding.