APPARATUS WITH A CURRENT-GAIN LAYOUT
An apparatus including separate first and second active regions that are physically separate, with each region including one or more sets of doped regions that each define a current channel. The current channels on the first and second active regions are activated by a common gate signal.
This application is a continuation of U.S. application Ser. No. 16/234,358, filed Dec. 27, 2018; which is incorporated herein by reference in its entirety.
TECHNICAL FIELDThe disclosed embodiments relate to devices, and, in particular, to semiconductor devices with a current-gain layout.
BACKGROUNDSemiconductor devices (e.g., transistor devices) can include semiconductor circuits configured to switch electronic signals. The transistor devices can include at least three terminals (e.g., gate, source, and drain) that connect to external circuits. To operate the transistor devices, voltage is controlled across a pair of the terminals, which controls the current through another pair of terminals. Accordingly, the transistor devices can operate in a first state that enables current flow across the terminals and a second state that restricts the current flow. For example, in transistor devices, electric current from the source terminal to the drain terminal can be restricted when a voltage, that is lower than a threshold voltage, is applied between the gate and source terminals.
The transistor devices can be configured to provide a targeted amount of current (e.g., drain-source current (IDs)) through the corresponding terminals (e.g., drain and source). For example, a layout, a total number of channels, a size of the channel, etc. of the transistor devices can be controlled to provide the targeted amount of current.
The first transistor unit 102 can include a gate 122 attached to the substrate 112 between a source 124 and a drain 126. The gate 122 can be the terminal or the electrical connection that supplies the control voltage (e.g., a specific voltage relative to the source 124) that regulates the operating state of the first transistor unit 102. According to the gate voltage, the drain-source current can flow between the drain 126 and the source 124. For transferring the current in and out of the circuit, the first transistor unit 102 can include conductive structures (e.g., a terminal pad, a trace, etc.) that form and/or connect to the drain 126 and the source 124, such as at contact regions 116.
The first transistor unit 102 can further have a size or a dimension that influences the amount of drain-source current. For example, the first transistor unit 102 can correspond to a first width 132 (D1) that is orthogonal to a current flow direction 134 that goes across the gate 122 between the source 124 and the drain 126. The first width 132 can represent a size of the current corridor or a number of electrons that can simultaneously travel across the source 124 and the drain 126. Accordingly, the width of the transistor can be a parameter that influences its drain-source current capacity.
As illustrated in
For illustrative purposes, the first transistor unit 102 and the transistor device 152 are shown with six contacts per each drain and source. Also for illustrative purposes, the first transistor device 152 is shown having four current channels. However, it is understood that the first transistor unit 102 and the transistor device 152 can have any number of contacts and/or current channels.
The first sub-unit 204 and the second sub-unit 206 can both have a second width 232 (D2) along a direction orthogonal to a current flow direction 234. For comparison, the second width 232 can be half of the first width 132 of
While the total width may be identical (along with other characteristics, such as contact size/spacing, substrate characteristics, biasing characteristics, etc.) across the first transistor unit 102 and the second transistor unit 202 (i.e., when the sub-units 204 and 206 are electrically connected), the second transistor unit 202 can provide increased source-drain current based on the additional current channel therein. In other words, the second transistor unit 202 can be larger in current gain than the first transistor unit 102.
In comparing the first transistor device 152 of
As described in greater detail below, the technology disclosed herein relates to semiconductor devices, systems with semiconductor devices, and related methods for providing a current-gain layout in the semiconductor devices. In the embodiments described below, the semiconductor devices (e.g., transistors) can include sectional transistor devices that have at least two separate sections (e.g., substrates) that are tied by continuous and/or straight conductive structures for its gate, source, and drain regions. In other words, the sectional transistor devices can include two or more current channels or transistor units connected in series.
The first section 304 can include a first substrate (or active region) 312 and the second section 306 can include a second substrate (or active region) 314 that are separate (e.g., non-contiguous bodies of semiconductive material) from each other. In some embodiments, the sectional transistor device 302 can include a shallow trench isolation (STI) between the first section 304 and the second section 306 that separates the two sections. The first substrate 312 and the second substrate 314 can each include regions that are doped to form sources and drains. The sectional transistor device 302 can include conductive structures (e.g., wires, traces, pads, etc.) that connect to the doped regions. For example, a gate connector 322 (e.g., a conductive structure having multiple legs/extensions) can be connected to the gates between each pairing of source and drain. Also, at various contacts 316, a source connector 324 can directly contact the source regions of the substrates and a drain connector 326 can directly contact the drain regions of the substrates.
Also, the first section 304 and the second section 306 can each include current channels that are arranged parallel to each other, such as in rows or columns. The first section 304 can include current channels that have a first section width 334 (D3), and the second section 306 can include current channels that have a second section width 336 (D4). Further, the first section 304 and the second section 306 can be separated by a separation distance 338 such as STI.
In some embodiments, the first section 304 and the second section 306 can arranged such that the current channels of the first section 304 extend along a first line and the current channels of the second section 306 extend along a second line. For example, for the embodiment illustrated in
Based on connecting a set of current channels, the sectional transistor device 302 can provide the increased number of current channels without the increasing the interconnects. For comparison to the first transistor device 152 of
Since the total channel width of the current channels in the col-linear set affects the drain-source current, the difference in the first section width 534 and the second section width 536 does not affect the drain-source current. For comparison, in order to match the 2 μm channel width of the first transistor unit 102 of
In some embodiments, the input buffer 700 can be employed at a data (DQ) connection in a memory device (e.g., a dynamic random-access memory (DRAM) 701).
The input buffer 700 can include one or more transistors (e.g., N-channel transistors and/or P-channel transistors) configured to receive and process corresponding input signals such as a write enable signal, a DQ system signal (e.g., DQSB, DQST, etc.), the data (DQ) signal, or a combination thereof. In some embodiments, the DQ system signal can include the DQSB signal corresponding to a bar signal of a data strobe signal (DQS), the DQST corresponding to a true signal of DQS, or a combination thereof. Accordingly, the input buffer 700 can generate an output signal based on receiving and processing the input signals.
In some embodiments, the input buffer 700 can include a P-channel transistor (M31) controlled by the write enable signal (e.g., supplied to a gate of M31) to connect a supply voltage (VDD; e.g., connected to a source of M31) to the other transistors. For example, M31 can be OFF when the write enable signal is at an inactive high level, such as when no data signal to be written is supplied to the input buffer 700, thereby reducing a leakage current. A source of another P-channel transistor (M30; controlled by the DQSB supplied to a gate thereof) can be connected to a drain of M31. A drain of M30 can be connected to sources of one or more further P-channel transistors (M1 and/or M2) operated by the DQ signal connected to gates thereof. In one or more embodiments, M1 and/or M2 can be a differential amplifier or a portion thereof such that the gate of M1 is connected to a positive connection of the DQ signal and M2 is connected to a negative connection of the DQ signal (e.g. a reference node (Vref)). Drains of M1 and/or M2 can be connected to ground through corresponding precharging transistors (e.g., N-channel transistors M7 and M8, respectively) that are operated by the DQST signal connected to the gates of the M7 and/or M8. The precharging transistors (M7, M8, M30, M27, M28, M29, or a combination thereof) can be operated according to a data strobe signal (DQS) or derivatives thereof (e.g., the DQST and/or the DQSB signals) to precharge the respective nodes.
In some embodiments, the drains of M1 and/or M2 can further be connected to gates of corresponding N-channel transistors (M26 and M27, respectively) for further amplifying an output of the differential amplifier (e.g., M1 and M2). Sources and drains of the amplifying transistors (M26 and/or M27) can be connected to a series of transistors connected to a source of M31 and a drain of M30. For example, the sources of the amplifying transistors M26 and/or M27 can be connected to ground through one or more current control transistors (e.g., N-channel transistors M40 and/or M41). Also, the drains of the amplifying transistors M26 and/or M27 can be connected to one or more latching transistors (e.g., M14, M15, M16, and/or M17 for holding logic level amplified by M1, M2, M26, and/or M27) and/or one or more precharging transistors (e.g., M28 and/or M29). In some embodiments, sources of the latching transistors and/or the precharging transistors (e.g., M14, M15, M28, and/or M29) can be connected to the drain of M31 and the source of M30. Drains of the upstream output transistors can generate the output signal. For example, the drains of M28 and M14 can generate a differential high portion of the output signal (OUT+) and the drains of M29 and M15 can generate a differential negative portion of the output signal (OUT−). One or more of the upstream output transistors (e.g., M14 and/or M15) can be operated according to the opposing differential output connected to the gates thereof. For example, the gate of M14 can be connected to OUT− and/or the gate of M15 can be connected to OUT+. Some of the other upstream output transistors (e.g., M28 and/or M29) can be operated according to the DQST signal connected to the gates thereof. In some embodiments, the nodes that corresponding to OUT+ and/or OUT− can be further connected to one or more downstream transistors (e.g., N-channel transistors M16 and/or M17). For example, drain of M16 can be connected to the OUT+ node, and drain of M17 can be connected to the OUT− node. Also, source of M16 can be connected to drain of M26, and source of M17 can be connected to drain of M27. The gates of the downstream transistors can be operated by the opposing differential output, such as by having gate of M16 connected to the OUT− node and by having gate of M17 connected to the OUT+ node.
The input buffer 700 can include the sectional transistor device 302 for one or more of the transistors described above. For example, the sectional transistor device 302 can be used at one or more locations in the DQ input buffer, such as for amplifying the logic level (e.g., increasing a gain to operate at a high speed). In one or more embodiments, the sectional transistor device 302 can be used to initially receive the DQ signal, such as for the P-channel transistors M1 and/or M2 where the DQ signal is connected to the gate connector 322. In one or more embodiments, one or more sets of the sectional transistor device 302 can be implemented in the DQ input buffer as differential amplifiers (e.g., M1 and/or M2), second stage amplifier (e.g., M26 and M27), etc.
At block 802, a semiconductor substrate (e.g., silicon, germanium, etc.) can be provided. At block 804, various regions of the semiconductor substrate can be doped to form one or more current channels. For example, different regions of the semiconductor substrate can be doped using acceptors or p-type dopants (e.g., boron, aluminum, gallium, etc.), donors or n-type dopants (e.g., phosphorous, arsenic, lithium, etc.), or other dopants. Also, the various regions can be doped to form doped substrate, wells, depletion layer, and/or other doped regions that correspond to the source, the gate, the drain, etc. The various regions (e.g., the source regions, the gate regions, the drain regions, etc.) can be formed extending along a common direction such that the resulting current channels are parallel to each other. For example, the substrate can be doped to form alternating columns/rows of source and drain with a gate region between abutting a pair of sour-drain or drain-source.
At block 806, the semiconductor substrate can be separated to form a targeted number of separate substrates that include at least a first substrate (e.g., the first substrate 312 of
In some embodiments, such as represented at block 822, the isolation mechanism can be formed at a location that corresponds to targeted channel widths (e.g., the first channel width, the second channel width, the third channel width, etc.) for the first and second current channels. Further, the isolation mechanism can be formed having a dimension that corresponds to the separation distance 338 of
At block 808, one or more conductive structures can be formed to electrically connect matching or corresponding regions across the first and second substrates. For example, a gate connector (e.g., a trace, a contact, a pad, etc.) can be formed (e.g., via depositing conductive metal) connecting a set or all of the gate regions on the divided substrates. Similarly, a source connector and a drain connector can be formed connecting the source regions and the drain regions, respectively. Forming each of the connectors can include forming one or more legs that each correspond to a current channel, such as illustrated at block 832. Each of the legs can be formed extending along a direction (e.g., a direction parallel to the channel width) across the divided sections and the isolation mechanism. For example, each of the legs can be directly over and extend along the corresponding regions of a set of current channels.
The method 800 is illustrated using some of the processing steps in an example order. However, one of ordinary skill in the art can appreciate that the method 800 includes other associated steps (e.g., masking, planarization, etc.) associated with semiconductor processing. Further, in some embodiments, the method of manufacture can be different. For example, the various substrates can be separately provided, processed (e.g., doped) and then attached to opposing sides of the isolation mechanism such that the current channels are parallel.
From the foregoing, it will be appreciated that specific embodiments of the technology have been described herein for purposes of illustration, but that various modifications may be made without deviating from the disclosure. In addition, certain aspects of the new technology described in the context of particular embodiments may also be combined or eliminated in other embodiments. Moreover, although advantages associated with certain embodiments of the new technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.
In the illustrated embodiments above, the sectional transistor devices have been described in the context of CMOS devices. Transistor devices configured in accordance with other embodiments of the present technology, however, can include other types of suitable transistor types in addition to or in lieu of CMOS devices, such as, FET, MOSFET, or BJT devices, etc.
The term “processing” as used herein includes manipulating signals and data, such as writing or programming, reading, erasing, refreshing, adjusting or changing values, calculating results, executing instructions, assembling, transferring, and/or manipulating data structures. The term data structures includes information arranged as bits, words or code-words, blocks, files, input data, system generated data, such as calculated or generated data, and program data. Further, the term “dynamic” as used herein describes processes, functions, actions or implementation occurring during operation, usage or deployment of a corresponding device, system or embodiment, and after or while running manufacturer's or third-party firmware. The dynamically occurring processes, functions, actions or implementations can occur after or subsequent to design, manufacture, and initial testing, setup or configuration.
The above embodiments are described in sufficient detail to enable those skilled in the art to make and use the embodiments. A person skilled in the relevant art, however, will understand that the technology may have additional embodiments and that the technology may be practiced without several of the details of the embodiments described above with reference to
Claims
1. An apparatus, comprising:
- a first active region including a first set of regions configured to selectively provide a first current channel according to a gate signal;
- a second active region including a second set of regions configured to selectively provide a second current channel according to the gate signal, wherein: the first and second active regions have same dopants and are physically separate, and the first and second current channels correspond to parallel current flow directions; and
- conductive structure linearly extending across and electrically connecting matching regions within the first and second sets of regions, wherein the conductive structure linearly extends along a direction orthogonal to the parallel current flow directions.
2. The apparatus of claim 1, wherein:
- the first set of regions are configured to selectively provide a first adjacent channel according to the gate signal, wherein the first adjacent channel is (1) physically separate and adjacent to the first current channel and (2) extends along the parallel current flow directions;
- the second set of regions are configured to selectively provide a second adjacent channel according to the gate signal, wherein the second adjacent channel is (1) physically separate and adjacent to the second current channel and (2) extends along the parallel current flow directions; and
- the conductive structure includes a first linear leg and a second linear leg electrically connecting the first current channel, the second current channel, the first adjacent channel, and the second adjacent channel in parallel, wherein the first linear leg and the second linear leg extend along the direction orthogonal to the extends along the parallel current flow directions.
3. The apparatus of claim 1, wherein:
- the first set of regions includes a first source region and/or a first drain region associated with the first current channel;
- the second set of regions includes a second source region and/or a second drain region associated with the second current channel; and
- the conductive structure includes a linear leg that extends across the first active region and the second active region, wherein the linear leg is directly over and electrically connects either the first and second source regions or the first and second drain regions.
4. The apparatus of claim 3, wherein:
- the first set of regions includes a first gate region configured to receive and operate according to the gate signal; and
- the second set of regions includes a second gate region configured to receive and operate according to the gate signal.
5. The apparatus of claim 1, further comprising:
- an isolation mechanism between the first active region and the second active region, wherein the isolation mechanism physically separates the first current channel from the second current channel; and
- wherein:
- the conductive structure extends across the isolation mechanism.
6. The apparatus of claim 5, wherein the isolation mechanism is a shallow trench isolation (STI) mechanism.
7. The apparatus of claim 1, wherein:
- the first current channel has a first channel width; and
- the second current channel has a second channel width different than the first channel width.
8. The apparatus of claim 1, wherein the first current channel has a first channel width and the second current channel has a second channel width equal to the first channel width.
9. The apparatus of claim 1, wherein the first current channel has a first channel width and the second current channel has a second channel width, wherein a sum of the first channel width and the second channel width is a total channel width associated with a source-drain current level for the apparatus.
10. The apparatus of claim 1, further comprising:
- a third active region including a third set of regions configured to selectively provide a third current channel according to the gate signal, wherein: the third active region has the same dopant as the first and second active regions and is physically separate from the first and second active regions, and the third current channel extends parallel to the parallel current flow directions; and
- wherein:
- the conductive structure linearly extends across the third active region and electrically connects matching regions within the first, second and third sets of regions.
11. The apparatus of claim 1, wherein the first active region, the second active region, and the conductive structure comprise a transistor device.
12. The apparatus of claim 11, wherein the transistor device comprises a data input buffer of the DRAM device.
13. The apparatus of claim 12, wherein the transistor device comprises an amplifier circuit in the data input buffer.
14. The apparatus of claim 1, wherein selectively providing the first and second current channels includes activating the first and second current channels in response to the gate signal.
15. An apparatus, comprising:
- a first active region comprising (1) a first set of regions cooperating with each other to define a first current channel and (2) a second set of regions cooperating with each other to define a second current channel;
- a second active region comprising (1) a third set of regions cooperating with each other to define a third current channel and (2) a fourth set of regions cooperating with each other to define a fourth current channel, the second active region being isolated from the first active region, wherein the first, second, third, and fourth current channels extend along a first direction;
- a gate electrode comprising first and second fingers, the first finger extending along a second direction and over the first and third current channels, and the second finger extending along the second direction and over the second and fourth current channels;
- a first electrode comprising third and fourth fingers, the third finger extending in the second direction and defining ends of the first and third current channels, the fourth finger extending in the second direction and defining ends of the second and fourth current channels; and
- a second electrode comprising a fifth finger, the fifth finger extending in the second direction and defining opposing ends of the first, second, third, and/or fourth current channels.
16. The apparatus of claim 15,
- wherein regions in each of the first, second, third, and fourth sets of regions are arranged along the first direction;
- wherein first matching regions in the first and third sets of regions are arranged along a first line that extends along the second direction; and
- wherein second matching regions in the second and fourth sets of regions are arranged along a second line that extends along the second direction.
17. The apparatus of claim 15, wherein the first, second, third, and fourth sets of regions each include a source region, a gate region, and/or a drain region.
18. The apparatus of claim 15, wherein the first, second, third, and fourth current channels are activated according to a gate signal.
19. The apparatus of claim 15, wherein the second active region is isolated from the first active region by a shallow trench isolation (STI).
20. The apparatus of claim 16, wherein the first electrode serves as a source electrode and the second electrode serves as a drain electrode.
Type: Application
Filed: Oct 21, 2020
Publication Date: Feb 4, 2021
Inventor: Takashi Ishihara (Tokyo)
Application Number: 17/076,626