Abstract:
A package for flat lead transistors is provided in which a raised flange provides structural rigidity to prevent damage to the flat leads of the transistor.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     The manufacture of packages in which semiconductor devices, particularly those with flat leads, may be shipped has been a problem. Heretofore such devices have typically been shipped in packages such as polyethylene bags which offer little protection to the flat leads, or rigid boxes which offer protection but are expensive to manufacture. 
     In accordance with the illustrated preferred embodiment, the present invention provides a package in which semiconductor devices, including those with flat leads, may be simply contained while protection is provided against bending of the leads. The preferred structure is of a flexible material such as plastic and includes a hollow central region to house the main body of the semiconductor device, and a flat portion against which the leads of the device are contrained, e.g., by means of a strip of tape. Structural rigidity is provided to the package by an outer flange. A number of such structures may be included in a single strip, thereby enabling the efficient packaging of semiconductor devices. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective drawing including a cross-section of a preferred embodiment of a package element taken along a line A--A in FIG. 2. 
     FIG. 2 illustrates a package including a number of package elements arranged in a strip. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In FIG. 1 there is illustrated a piece of packaging material 11, for example thin plastic sheets of thickness about 0.01 inches. A raised central area 13 and a raised ridge or flange-like portion 15 are stamped into sheet 11 in accordance with processes well known in the art. In the preferred embodiment of FIG. 1 both of the raised portions are shown as being essentially circular and having conical cross-sections. However, it will be evident to those skilled in the art that other configurations may be employed. 
     A semiconductor device 17 such as a microwave transistor is also illustrated in FIG. 1. Transistor 17 is shown as including four flat leads, labeled 19, 20, 21, and 22. In the packaging of transistor 17, the central portion of the transistor is fitted into central region 13 of the package. Flat leads 19, 20, 21, and 22 are brought into contact with a region 23 of the bottom of sheet 11 between raised regions 13 and 15. The transistor is held in place by a piece of restraining material 27, e.g., a thin piece of tape. 
     Construction of a package according to these principals provides protection against bending of the flat leads. More particularly, it has been found that the raised ridge 15 prevents bending of sheet 11 in the interior region 23 adjacent to the flat leads even when the sheet is generally subjected to bending forces. Thus, the flat leads are prevented from bending or other deformation. 
     In FIG. 2 there are shown a number of structures such as that described in FIG. 1, these structures being arranged in strip-like fashion on one piece of material 11. This arrangement makes possible the inexpensive fabrication of the package and also provides for the simple packaging of a large number of transistors.