Patent ID: 9331037
Filing Date: 2016-05-03
CPC Classification: H01L

Claim Text:
1. A method of making a semiconductor die contact assembly, the method comprising: providing a first stage assembly; removing a photoresist layer from the first stage assembly to yield a second stage assembly; and removing a portion of a ball limiting metallurgy layer from the second stage assembly to yield a third stage assembly; wherein: the first stage assembly includes the ball limiting metallurgy layer, a first thick pad, the photoresist layer, and a first pre-reflow solder structure; in the first and second stage assemblies, the ball limiting metallurgy layer defines a top surface; in the first stage assembly, the photoresist layer: (i) is located on top of the top surface of the ball limiting metallurgy layer, (ii) defines a first pocket located over the first thick pad, and (iii) defines a first upstanding wall defining the first pocket; in the first stage assembly, the pre-reflow solder structure is located within the first pocket and over a portion of a footprint of the first thick pad; in the first stage assembly, an entirety of the first upstanding wall extends upwards from a first region of the top surface of the ball limiting metallurgy layer; in the first stage assembly, no portion of the first region of the top surface of the ball limiting metallurgy layer is located on any downward-inclined discontinuity; and a thickness of the first thick pad is substantially greater than 1 micrometer.