摘要:
In some embodiments, an apparatus includes: a first layer (145) with a first surface (144); and a second surface opposite to the first surface. The apparatus also includes a second layer (140) having: a third surface interfacing the second surface; and a fourth surface opposite the third surface. The apparatus further includes a third layer (150) having: a fifth surface interfacing the fourth surface; and a sixth surface opposite the fifth surface. The apparatus also includes a fourth layer (160) having a seventh surface interfacing the sixth surface to form a heteroj unction, which generates a two-dimensional electron gas channel formed in the fourth layer. Further, the apparatus includes a recess (146, 147, 149) that extends from the first surface to the fifth surface.
摘要:
Techniques related to III-N transistors having improved performance, systems incorporating such transistors, and methods for forming them are discussed. Such transistors include first and second crystalline III-N material layers separated by an intervening layer other than a III-N material such that the first crystalline III-N material layer has a first crystal orientation that is inverted with respect to a second crystal orientation of the second crystalline III-N material layer.
摘要:
Semiconductor devices including III-N transistors adjacent to III-N substrate taps extending from a group IV heteroepitaxial growth substrate are described. In embodiments, GaN mesas that are to host conductive substrate taps are grown concurrently with GaN mesas that are to host transistors. A GaN mesa for a substrate tap is then selectively doped, for example with a masked implant. An intrinsic GaN mesa for a transistor is then selectively processed, for example to form a transistor channel. Heavily doped semiconductor may then be grown on all GaN mesas and contact metallization landed on the heavily doped semiconductor. Backend interconnect levels may then be successively landed on the substrate tap to maintain an electrical path to the substrate sufficient to mitigate charging-related damage to the transistors during backend processing.
摘要:
Techniques are disclosed herein for ferroelectric-based field-effect transistors (FETs) with threshold voltage (VT) switching for enhanced RF switch transistor on-state and off-state performance. Employing a ferroelectric gate dielectric layer that can switch between two ferroelectric states enables a higher VT during the transistor off-state (VT,hi) and a lower VT during the transistor on-state (VT,lo). Accordingly, the transistor on-state resistance (Ron) can be maintained low due to the available relatively high gate overdrive (Vg,on - VT,lo) while still handling a relatively high maximum RF power in the transistor off-state due to the high VT,hi - Vg,off value. Thus, the Ron of an RF switch transistor can be improved without sacrificing maximum RF power, and/or vice versa, the maximum RF power can be improved without sacrificing the Ron. A ferroelectric layer (e.g., including Hf x Zr y O) can be formed between a transistor gate dielectric layer and gate electrode to achieve such benefits.
摘要:
Techniques are provided for forming a semiconductor device. In an aspect, a semiconductor device (100) is provided that includes a silicon carbide (SiC) structure (102) and a III-nitride structure (104). The SiC structure includes a drain electrode (106), a substrate layer (108) that is formed on the drain electrode and includes SiC, and a drift layer (110) formed on the substrate layer. The drift layer includes p-well regions (112a, 112b) that allow current to flow through a region (134) between the p-well regions. The III-nitride structure includes a set of III-nitride semiconductor layers formed on the SiC structure, a passivation layer (1608) formed on the set of III-nitride semiconductor layers, a source electrode (126) electrically coupled to the p-well regions, and gate electrodes (1606a, 1606b) electrically isolated from the set of III-nitride semiconductor layers. In an aspect, the SiC structure includes a transition layer (111) that includes connecting regions (114a, 114b). In another aspect, the III-nitride structure includes connection electrodes (130a, 130b) electrically coupled to the connecting regions.
摘要:
A semiconductor device includes a layered structure forming multiple carrier channels extending in parallel at different depths of the semiconductor device and a gate electrode having multiple gate fingers of different lengths penetrating the layered structure to reach and control corresponding carrier channels at the different depths. The semiconductor device also includes a carrier electrode having multiple carrier fingers of different lengths penetrating the layered structure to access the corresponding carrier channels. The carrier fingers are interdigitated with the gate fingers.
摘要:
In described examples, a semiconductor device (100) containing an enhancement mode GaN FET (102) on a III-N layer stack includes a low-doped GaN layer (112), a barrier layer (114) including aluminum over the low-doped GaN layer, a stressor layer (116) including indium over the barrier layer, and a cap layer (118) including aluminum over the stressor layer. A gate recess (120) extends through the cap layer (118) and the stressor layer (116), but not through the barrier layer (114). The semiconductor device (100) is formed by forming the barrier layer (114) with a high temperature MOCVD process, forming the stressor layer (116) with a low temperature MOCVD process, and forming the cap layer (118) with a low temperature MOCVD process. The gate recess (120) is formed by a two-step etch process including a first etch step to remove the cap layer (118), and a second etch step to remove the stressor layer (116).