Motorola Corporation

Jenny M Ford

Zhirong Tang

Heemyong Park

David Joseph Monk

Robert H Reuss

John W Steele

Clarence A Lund

An n-channel device ( ) and a p-channel device ( ) are formed from a single epitaxial silicon layer ( ). During the deposition of the single epitaxial silicon layer ( ), dopants are added to the epitaxial reaction chamber and subsequently changed to define a drain region ( ), a channel region ( ), and a source region ( ). The dopant concentration is modified during the formation of the channel region ( ) to create a doping profile ( ). The doping profile ( ) has a first profile ( ) that is constant and a second profile ( ) that changes.

Method of manufacturing vertical semiconductor device

An n-channel device (10) and a p-channel device (11) are formed from a single epitaxial silicon layer (60,61). During the deposition of the single epitaxial silicon layer (60,61), dopants are added to the epitaxial reaction chamber and subsequently changed to define a drain region (24,33), a channel region (27,34), and a source region (30,35). The dopant concentration is modified during the formation of the channel region (27,34) to create a doping profile (50). The doping profile (50) has a first profile (51) that is constant and a second profile (52) that changes.

Vertical semiconductor device and method of manufacturing the same

Vertical semiconductor device

A heterojunction bipolar transistor (HBT) (30) is formed to have a germanium composition profile (46) in a base region (32) that improves the tolerance of the HBT device (30) to manufacturing variations and reduces the sensitivity to emitter/base biases. A first region (40) of essentially constant germanium composition is formed at the interface of an emitter region (34) and the base region (32). The germanium composition profile (46) also has a second region (41) in which the germanium composition is increased linearly to provide an acceleration field by reducing the band gap in this second region (41). The acceleration field reduces the transit time of carriers and increases the frequency response of the HBT device (30).

Heterojunction semiconductor device and method of manufacture

A transistor (10) is formed by utilizing an isolated well (18) within a thin epitaxial layer (14). A base mask (22) that has a base opening (23) is applied to expose a portion of the isolated well (18). A low resistance collector enhancement (24) is formed within the well (18) by doping a portion of the well (18) through the base opening (23). A base region (26) is formed overlying the collector enhancement (24) by doping the well (18) through the base opening (23). Forming the collector enhancement (24) through the base opening (23), facilitates providing the collector enhancement (24) with a small area thereby minimizing the transistor's (10) parasitic collector capacitance value, collector resistance, and transit time.

Forming a vertical PNP transistor

An improved bipolar transistor of a BiCMOS integrated circuit is fabricated by utilizing a shallow trench structure. The shallow trench defines an active base and a self-aligned emitter. The base resistance of the transistor is reduced because a vertical, rather than lateral, link base, which connects an extrinsic base to the active base, is formed. In addition, the overall area is reduced, which provides for a lower collector to base capacitance.

Process for making BiCMOS integrated circuit having a shallow trench

An active portion of a cell of a static RAM semiconductor device comprising a MOSFET and a variable resistor load device having non-diffused contacts which are self-aligned is described. A polycrystalline gate is used as a mask for the implantation of a source and a drain into a semiconductor substrate. Following the formation of a conformal dielectric layer and a conformal polycrystalline layer PtSi contacts are formed. These contacts are also aligned by the gate and do not diffuse and therefore may be spaced closely together. As the MOSFET of the device is turned 'on' and 'off' the resistance of the load device increases and decreases proportionately.

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Mesa, AZ, United States of America

Jenny M Ford