BORON-NITRIDE COATED THERMODE BLADE FOR SURFACE-MOUNTED TECHNOLOGY INTERCONNECTIONS
Original Publication Date: 1988-Aug-01
Included in the Prior Art Database: 2005-Feb-15
Titanium thermode blades (hot-bar) are currently used in Surface-Mounted Component (SMC) assembly lines to reflow solder and to bond quad flat packs onto standard printer circuit boards. The hot bar is resistively heated by passing current, and heat is transferred across its surface to the component leads, solder, and copper lands. The problems associated with the use of titanium as a blade material are: (a) the possibility of electrical current being leaked out from the blade and causing damage to the chips when the hot blade touches the flat-pack's outer leads, (b) titanium blades tend to get dirty from flux and solder residue collecting on them during bonding operation, and have to be cleaned frequently (e.g.