JPS636851A - Very thin semiconductor device - Google Patents

Abstract

PURPOSE:To remove a pad electrode from the surface of an activated region and to enable the total thickness of a device to be determined only by a thickness of a semiconductor element, by forming the element so as to have a trapezoidal cross section and extending a bump electrode connecting conductor downwards to the surface of a film-type external lead. CONSTITUTION:In a very thin semiconductor device, a semiconductor element 1 has a trapezoidal cross section so that there is no pad electrode on the surface of the element 1 including an activated region. A passivation film 4 is therefore allowed to cover all the regions sufficiently, which eliminates the need of providing a thick molded coat. Further, since each conductor 2 for interconnecting the bump electrode is extended downwards along the inclined face of the element to the position of a film-type external lead 3, the total thickness of the device can be determined by the thickness of the element 1 itself.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device with an ultra-thin structure suitable for manufacturing IC cards and the like.

[Conventional technology]

Conventionally, thin semiconductor devices of this type have either been made by forming a vertical groove on the printed circuit board and storing the semiconductor element in this groove, or by placing the semiconductor element facing downward and connecting its bump electrodes to the printed wiring. made by any of the following methods. In other words, this can be achieved by devising a mounting method on a printed circuit board without making any changes to the shape of the semiconductor element.

[Problem that the invention seeks to solve]

However, the former structure in which semiconductor elements are housed within a printed circuit board has a thickness of approximately 900 pm.

Furthermore, even with the latter structure in which the bank electrode is directly connected to the print distribution, the thickness can only be reduced to about 800 μm, so if only the devised mounting method is used, it will not be possible to meet the recently proposed ISO standard (draft) 0. .76-thick IC cards would be extremely difficult to implement.

In view of the above circumstances, the object of the invention is to develop an ultra-thin semiconductor device with a thickness of 1 ft. that can easily achieve at least the thinning of an IC card.
By providing it.

[Means for solving problems]

The uninvented ultra-thin semiconductor device includes a semiconductor element having a trapezoidal cross section, a bump electrode wiring conductor provided along an inclined surface of the semiconductor element, and a film connected to the tip of the bump electrode wiring conductor. The method further includes: a shaped external lead conductor; and a pagsi conductor coating covering the entire surface of the semiconductor device including the activation area.

In a semiconductor device having such a structure, since the pad 11 does not exist on the surface including the active region of the semiconductor element, the packed base film is provided not only on the active region surface but also along the aluminum wiring and the inclined surface of the element. All other areas including the wiring conductor for bump electrodes are fully covered, eliminating the need for a thick mold coat. Since it is sufficiently lowered to the position of the leads, the thickness of the entire semiconductor device can almost be determined by the thickness of the semiconductor element itself.

Therefore, an ultra-thin semiconductor device with a thickness of 700 pm or less can be realized very easily while maintaining sufficient reliability.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

FIG. 1 (al and (bl) are a sectional view and a plan view, respectively, showing an embodiment of the invention. According to this embodiment, an ultra-thin semiconductor device of the present invention includes a semiconductor element 1 having a trapezoidal cross section. , a bump electrode wiring conductor 2 provided along the inclined surface of the semiconductor element 1 , a film-shaped external lead 3 connected to the tip of the bump electrode wiring conductor 2 , an activated region of the semiconductor element 1 , It includes an aluminum wiring M (none of which is shown) and a badge page coating film (nitride film or borimide resin film) 4 formed to cover all surfaces including the bump electrode wiring conductor 2.Here, 5 Numeral 6 denotes a sanitary adhesive for firmly fixing the connecting portion between the bump electrode wiring conductor 2 and the film-shaped external lead 3, and 6 denotes an insulating film that covers the film-shaped external lead 3t.

According to this embodiment, the thickness of the entire semiconductor device is the semiconductor element l
The two thicknesses hl and h2, which are vertically divided with the connection surface of the film-like external lead 3 to the printed circuit board as a border, can be suppressed to be equal to about 300 μm. That is, an ultra-thin semiconductor device with a thickness of about 600 μm can be obtained. This thickness is sufficient to meet the currently proposed ISO standard (draft) for IC cards.

FIGS. 2 and 3 are sectional views showing other embodiments of the invention. That is, in FIG. 2, the semiconductor element 1 is placed on the opening of the printed circuit board 7 with the active region surface facing downward. Here, 8 indicates a printed wiring conductor on the printed circuit board 7. This structure has two thicknesses b3.
When h4 is 400 μm and 3QQ μm, the total thickness is about 700 μm, which is suitable for EEILOM. Further, FIG. 3 shows a semiconductor device 1 recoated with a thin mold sanitizing agent 9 to further improve reliability. Even in this case, the increase in the overall thickness is only about 100 μm at most, so it does not pose a major problem in mounting the IC card.

〔Effect of the invention〕

As explained in detail above, according to the present invention, the semiconductor 1
By making the cross section of the element trapezoidal, it is possible to remove the butt electrode from the surface of the activation region and to lower the wiring conductor for the bump electrode to the film-like external lead surface.
A semiconductor device whose overall thickness is uniquely determined by the thickness of the semiconductor element and whose reliability is improved can be easily realized.

In other words, a remarkable effect can be achieved in making the semiconductor device ultra-thin.

[Brief explanation of the drawing]

Figures 1 (al and b) are a cross-sectional view and a plan view showing one embodiment of the present invention, respectively, and Figures 2 and 3 are cross-sectional views showing other embodiments of the present invention, respectively. ...Semiconductor element, 2...Wiring conductor for bump electrode, 3...Film F outside i!, L-do, 4.Old...Pubscivation film, 5・・・・・・Street grease, 6・・・Insulating film, 7・・・・・・
Printed circuit board, 8...Printed wiring conductor, 9.
...Mold fat s hl * h2 ah
3mh4...Thickness. Figure 1

Claims (1)

[Claims] A semiconductor element having a trapezoidal cross section, a bump electrode wiring conductor provided along an inclined surface of the semiconductor element, a film-like external lead conductor connected to a tip of the bump electrode wiring conductor, and a semiconductor element having a trapezoidal cross section. An ultra-thin semiconductor device comprising: a passivation film covering the entire surface including an active region.