what is a semiconductor encapsulation ?
semiconductor packaging refers to the process of processing the tested wafers into individual chips according to the product type and functional requirements. t he encapsulation process is as follows: the wafers from the wafer pre-process are cut into small wafers (die) through the scribing process, and then the cut wafers are glued to the islands of the corresponding lead frames, and then the bond pads of the wafers are connected to the corresponding pins of the lead frames using ultra-ﬁne metal (gold, tin, copper and aluminum) wires or conductive resins, and form the required circuit. after sealing, a series of operations will be carried out, and the ﬁnished product will be tested after the sealing is completed.
what are the three major encapsulation for semiconductors?
the three main types of semiconductor packages are metal package, ceramic encapsulation , metal-ceramic encapsulation , and plastic encapsulation according to the materials used.
the ﬁrst major category: semiconductor metal encapsulation
metal encapsulation started with triode encapsulation , and then slowly applied to inline ﬂat encapsulation , which is basically a metal-glass assembly process. due to the strict size, high precision, metal parts for mass production, so its low price, excellent performance, encapsulation process is easy and ﬂexible, is widely used in transistors and hybrid integrated circuits such as oscillators, ampliﬁers, frequency converters, a c/dc converters, ﬁlters, relays and other products, now and in the future many micro encapsulation and multi-chip modules (mcm) also use this metal encapsulation . the types of metal encapsulation include optic electronics device package with optical window type, with lens type and with optical ﬁber type; jealousy device package including a type, b type and c type; mixed circuit package including double inline type and ﬂat type; special device package including momentary type, multi-layer multi-window type and non-magnetic material type.
the second major category: semiconductor ceramic encapsulation
in the early days of semiconductor encapsulation , ceramic encapsulation was the mainstay. a long with the development of highly integrated and high-speed semiconductor devices, the miniaturization of electronic devices and the reduction of prices, ceramic encapsulation was partially replaced by plastic encapsulation , but the multiple uses of ceramic encapsulation still have irreplaceable functions, especially the increase in the operating frequency of ntegrated circuit components, the acceleration of signal transmission speed and the increase in chip power consumption, requiring the selection of low resistivity wire conductor material, low dielectric constant, high conductivity insulation material, etc. are required. the types of ceramic packages are dip and sip; for large-scale integrated circuit packages include pga, plcc, qfp and bga.
the third major category: semiconductor plastic encapsulation
plastic encapsulation has a strong vitality due to its low cost, simple process, and suitable for mass production, so it has been developing faster and faster since its birth, and its share in packaging is increasing. currently, plastic encapsulation accounts for more than 95% of the ic market worldwide. the consumer circuit and device market is basically dominated by plastic encapsulation ; the industrial circuit market also accounts for a large proportion and has the largest variety of encapsulation forms. plastic packages include discrete device packages, including type a and type f, and integrated circuit packages, including sop, dip, qfp, and bga.