Electrical connectors with positioning mechanism

An electrical assembly comprising:

• an IC package module defining a plurality of downward conductive elements;
• an electrical connector located below the IC package and including a plurality of contacts having upper contacting portions upwardly communicating with the corresponding conductive elements, respectively;
• and
• complementary interengaging devices formed on both said IC package module and said connector;
• wherein
• when the IC package is assembled to the connector in a vertical direction, the complementary interengaging devices are initially coupled to each other, before the conductive elements of the IC package and the contacting portions of the contacts are coupled to each other, for assuring precise alignment between the IC package and the connector in said vertical direction and thus corresponding correct vertical coupling between the conductive elements and the corresponding contacting portions of the contacts, respectively, during the successive assembling in said vertical direction.