Semiconductor device and a method of manufacturing the same
View Patent ↗Provided is a semiconductor device comprising a first metal film formed above a semiconductor chip, a ball portion formed over said first metal film and made of a second metal, and an alloy layer of said first metal and said second metal which alloy layer is formed between said first metal film and said ball portion, wherein said alloy layer reaches the bottom of said first metal film, and said ball portion is covered with a resin; and a manufacturing method thereof. The present invention makes it possible to improve adhesion between the bonding pad portion and ball portion of a bonding wire over an interconnect, thereby improving the reliability of the semiconductor device.
1. A manufacturing method of a semiconductor device, comprising the steps of:
(a) forming a first metal film above a semiconductor chip region;
(b) forming over said first metal film an insulating film having an opening at a pad portion over said first metal film; and
(c) adhering a ball portion made of a second metal onto said pad portion such that part of said ball portion reaches the bottom of said pad portion by means of ultrasonic thermo-compression bonding at an ultrasonic frequency of 110 kHz or greater,
wherein said ultrasonic frequency is applied before said ball portion comes in contact with said pad portion; and
wherein a load is applied to said ball portion and is stepwise raised while applying said ultrasonic frequency.
2. A manufacturing method of a semiconductor device according to claim 1 , further comprising the step of, after said step (c):
(d) covering and sealing said ball portion with a resin.
3. A manufacturing method of a semiconductor device, comprising the steps of:
(a) forming a first metal film above a semiconductor chip region;
(b) forming over said first metal film an insulating film having an opening at a pad portion over said first metal film;
(c) upon formation of a ball portion made of a second metal over said first metal film such that part of said ball portion reaches the bottom of said first metal film, forming an alloy layer of said first metal and said second metal in at least 70% of a contact region of said first metal film with said ball portion, thereby adhering said ball portion onto said first metal film, and adjusting the shape of said ball portion so that a diameter d of said contact region and a maximum peripheral diameter D of said ball portion satisfy the following expression: d≧0.8D; and
(d) covering and sealing said ball portion with a resin,
wherein ultrasonic frequency is applied before said ball portion comes in contact with said first metal film; and
wherein a load is applied to said ball portion and is stepwise raised while applying said ultrasonic frequency.