Description:BACKGROUND
Field of Invention
[001] Embodiments of the present invention generally relate to an organic sensor and particularly to a biosensor for detecting biomolecules.
Description of Related Art
[002] Biosensors play a crucial role in modern diagnostics by enabling the detection of biomolecules with high sensitivity and specificity. Field-effect transistor (FET)-based biosensors, particularly those based on compound semiconductors like gallium nitride (GaN) and aluminum gallium nitride (AlGaN), have emerged as promising candidates due to their superior electrical properties and chemical stability. These biosensors operate by detecting surface charge variations induced by biomolecular interactions, resulting in a measurable change in channel conductivity. However, conventional FET biosensors suffer from several limitations, including low detection sensitivity, poor threshold voltage stability, and high leakage currents, making them less effective for applications requiring rapid and precise detection of low-concentration biomolecules.
[003] To address these limitations, researchers have explored various material and structural modifications in biosensor design. AlGaN/GaN high-electron-mobility transistors (HEMTs) have been widely adopted due to their high electron mobility and robustness in harsh environments. However, these structures face challenges such as inadequate confinement of the two-dimensional electron gas (2DEG), high sheet resistance, and difficulty in maintaining stable electrical characteristics over extended operational periods. In addition, the reliance on traditional substrates like silicon (Si) and sapphire can lead to lattice mismatch issues, resulting in increased defect densities and performance degradation. To enhance biosensor performance, recent advancements have focused on alternative barrier materials, back-barrier engineering, and improved substrate choices to optimize charge transport and detection capabilities.
[004] Further developments in the field have highlighted the importance of incorporating high-polarization materials and advanced back-barrier structures to improve charge carrier confinement and electrostatic control. Additionally, substrate selection plays a crucial role in ensuring thermal stability and minimizing lattice mismatches. While metal-organic chemical vapor deposition (MOCVD) has become the preferred fabrication technique due to its scalability and cost-effectiveness, optimizing the epitaxial growth process remains a critical challenge. As biosensing applications continue to demand higher sensitivity, faster response times, and greater reliability, innovative material combinations and device architectures are being investigated to overcome existing constraints and enhance the overall efficacy of biosensor technology.
[005] There is thus a need for an improved and advanced biosensor for detecting biomolecules that can administer the aforementioned limitations in a more efficient manner.
SUMMARY
[006] Embodiments in accordance with the present invention provide a biosensor for detecting biomolecules. The biosensor comprising a Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer adapted to enhance a spontaneous polarization and a charge accumulation at a heterointerface. The Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer is deposited on an Aluminium Gallium Nitride (AlGaN) layer. The biosensor further comprising a graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) adapted to confine a Two-Dimensional Electron Gas (2DEG) and stabilize threshold voltage shifts. The graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) is sandwiched between a Gallium Nitride (GaN) channel and an Iron (Fe) doped Gallium Nitride (GaN) buffer layer. The biosensor further comprising a Silicon Carbide (SiC) substrate adapted to sandwich the biosensor. The sandwiching of the biosensor improve a thermal dissipation and stability. The biosensor further comprising a functionalized gate region adapted to enable a real-time detection of biomolecular interactions through modulation of channel current. The gate region is etched on the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer.
[007] Embodiments in accordance with the present invention further provide a method for detecting biomolecules using a biosensor. The method comprising steps of functionalizing a gate region with a bio-receptive layer; introducing a sample containing target biomolecules; detecting changes in channel current due to biomolecular interactions; and analysing measured signal, due to the changes in the channel current, to determine a presence and a concentration of the target biomolecules.
[008] Embodiments of the present invention may provide a number of advantages depending on their particular configuration. First, embodiments of the present application may provide a biosensor for detecting biomolecules.
[009] Next, embodiments of the present application may provide a biosensor that enhances spontaneous and piezoelectric polarization, leading to a higher carrier density. This significantly improves charge modulation, enabling a detection of even extremely low-concentration biomolecules with high precision.
[0010] Next, embodiments of the present application may provide a biosensor that suppresses short-channel effects (SCEs) and prevents charge leakage into the buffer. This ensures better threshold voltage stability, a critical factor for reliable and repeatable biosensing applications.
[0011] Next, embodiments of the present application may provide a biosensor that improves heat dissipation and reduces thermal degradation, allowing the biosensor to operate efficiently in varying environmental conditions and high-power applications. This leads to long-term stability and durability.
[0012] Next, embodiments of the present application may provide a biosensor that features strong carrier confinement and charge modulation, accelerating biomolecule detection. This enables real-time, label-free sensing, making the biosensor ideal for medical diagnostics and environmental monitoring.
[0013] Next, embodiments of the present application may provide a biosensor that is fabricated using the MOCVD growth process, which is more cost-efficient and scalable compared to MBE. This allows for mass production with high-quality epitaxial layers, making the technology suitable for commercial applications.
[0014] These and other advantages will be apparent from the present application of the embodiments described herein.
[0015] The preceding is a simplified summary to provide an understanding of some embodiments of the present invention. This summary is neither an extensive nor exhaustive overview of the present invention and its various embodiments. The summary presents selected concepts of the embodiments of the present invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the present invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above and still further features and advantages of embodiments of the present invention will become apparent upon consideration of the following detailed description of embodiments thereof, especially when taken in conjunction with the accompanying drawings, and wherein:
[0017] FIG. 1 illustrates a schematic drawing of a biosensor for detecting biomolecules, according to an embodiment of the present invention; and
[0018] FIG. 2 depicts a flowchart of a method for detecting biomolecules using a biosensor, according to an embodiment of the present invention.
[0019] The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word "may" is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including but not limited to. To facilitate understanding, like reference numerals have been used, where possible, to designate like elements common to the figures. Optional portions of the figures may be illustrated using dashed or dotted lines, unless the context of usage indicates otherwise.
DETAILED DESCRIPTION
[0020] The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore, the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the scope of the invention as defined in the claims.
[0021] In any embodiment described herein, the open-ended terms "comprising", "comprises”, and the like (which are synonymous with "including", "having” and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of", “consists essentially of", and the like or the respective closed phrases "consisting of", "consists of”, the like.
[0022] As used herein, the singular forms “a”, “an”, and “the” designate both the singular and the plural, unless expressly stated to designate the singular only.
[0023] FIG. 1 illustrates a schematic drawing of a biosensor 100 for detecting biomolecules, according to an embodiment of the present invention. In an embodiment of the present invention, the biosensor 100 may be adapted to accommodate target molecules. Further, the presence of the target molecule may initiate changes in channel current of the biosensor 100. Further, the changes in the channel current may induce deviation in a signal of the biosensor 100. The induced deviation may be captured and analysed to determine a presence and a concentration of a target biomolecules.
[0024] The biosensor 100 may be a High-Electron-Mobility Transistor (HEMT)-based organic sensor. Embodiments of the present invention are intended to include or otherwise cover any class of the biosensor 100, including known, related art, and/or later developed technologies. The biosensor 100 may be applied in fields such as, but not limited to, medical diagnostics, environmental monitoring, biochemical analysis, and so forth. Embodiments of the present invention are intended to include or otherwise cover any field of application of the biosensor 100, including known, related art, and/or later developed technologies.
[0025] According to the embodiments of the present invention, the biosensor 100 may incorporate non-limiting hardware components to enhance the processing speed and efficiency such as the biosensor 100 may comprise a Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102, an Aluminium Gallium Nitride (AlGaN) layer 104, a graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) 106, a Gallium Nitride (GaN) channel 108, an Iron (Fe) doped Gallium Nitride (GaN) buffer layer 110, a Silicon Carbide (SiC) substrate 112a-112b, and a gate region 114. In an embodiment of the present invention, the hardware components of the biosensor 100 may be integrated with computer-executable instructions for overcoming the challenges and the limitations of the existing systems.
[0026] In an embodiment of the present invention, the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102 may be adapted to enhance a spontaneous polarization and a charge accumulation at a heterointerface. The Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102 may be adapted to charge density at the heterointerface, improving a sensitivity to the biomolecules. A sensitivity of the biomolecule detection may further be enhanced by optimizing a thickness and composition of the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102. A width of the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102 may be 6.5 nanometre.
[0027] In an embodiment of the present invention, the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102 may be deposited on an Aluminium Gallium Nitride (AlGaN) layer 104. A width of the Aluminium Gallium Nitride (AlGaN) layer 104 may be 2 nanometre.
[0028] In an embodiment of the present invention, the graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) 106 may be adapted to confine a Two-Dimensional Electron Gas (2DEG) and stabilize threshold voltage shifts. The graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) 106 may be adapted to Short-Channel Effects (SCEs) and prevents charge migration into the Iron (Fe) doped Gallium Nitride (GaN) buffer layer 110. A width of the graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) 106 may be 100 nanometre.
[0029] In an embodiment of the present invention, the Two-Dimensional Electron Gas (2DEG) density may reduce sheet resistance and may enhances electron mobility, contributing to the superior electrical performance of the biosensor 100. Additionally, a stronger built-in electric field at an interface may reinforce quantum confinement leading to minimizing carrier scattering and further improvements in biosensor 100 stability.
[0030] In an embodiment of the present invention, the graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) 106 may be sandwiched between the Gallium Nitride (GaN) channel 108 and the Iron (Fe) doped Gallium Nitride (GaN) buffer layer 110. A width of the Gallium Nitride (GaN) channel 108 may be 100 nanometres. A width of the Iron (Fe) doped Gallium Nitride (GaN) buffer layer 110 may be 1.5 picometer.
[0031] In an embodiment of the present invention, the Silicon Carbide (SiC) substrate 112a-112b may be adapted to sandwich the biosensor 100. The sandwiching of the biosensor 100 may improve a thermal dissipation and stability. The Silicon Carbide (SiC) substrate 112a-112b may be adapted to enhance thermal conductivity, ensuring stable operation across varying environmental conditions. The Silicon Carbide (SiC) substrate 112a-112b may be fabricated using Metal-Organic Chemical Vapor Deposition (MOCVD) to enable scalable and cost-effective manufacturing. A width of the Silicon Carbide (SiC) may be 5 picometer.
[0032] The Metal-Organic Chemical Vapor Deposition (MOCVD) may allow for the deposition of uniform and high-quality epitaxial layers over large wafer areas. The Metal-Organic Chemical Vapor Deposition (MOCVD) may exhibit lower defect densities due to better surface diffusion kinetics, leading to improved electrical performance and reliability.
[0033] In an embodiment of the present invention, the functionalized gate region 114 may be adapted to enable a real-time detection of biomolecular interactions through modulation of the channel current. The gate region 114 may be etched on the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer 102. The gate region 114 may comprise a bio-receptive layer that may selectively bind the target biomolecules, altering a local charge environment and modulating the channel current. The gate region 114 may be adapted to initiate a biomolecular binding event that may further result in a threshold voltage shift proportional to the concentration of the target biomolecules.
[0034] In an embodiment of the present invention, an improved threshold voltage (Vth) control may be essential for achieving stable and repeatable biomolecule detection with minimal drift over time in the biosensor 100. When biomolecules bind to the biosensor 100, the biomolecules may introduce localized charge variations that may modulate the electrostatic conditions at the gate region 114, leading to a measurable shift in Vth. This shift may directly influence the Two-Dimensional Electron Gas (2DEG) density, resulting in corresponding changes in drain current (ID) and transconductance (gm), both of which serve as key detection parameters. Since Vth may be directly linked to carrier concentration in the Two-Dimensional Electron Gas (2DEG), even small changes due to the biomolecule interaction may be precisely detected. Precise control over Vth may ensure that these variations remain consistent and predictable, allowing for accurate correlation between biomolecule concentration and electrical response. Additionally, stable Vth minimizes false readings and reduces long-term drift, ensuring high reproducibility across multiple detection cycles. By maintaining a well-defined and controlled threshold voltage, the biosensor 100 may achieve enhanced sensitivity, reliability, and repeatability, making it ideal for real-time, label-free biomolecule detection.
[0035] FIG. 2 depicts a flowchart of a method 200 for detecting the biomolecules using the biosensor 100, according to an embodiment of the present invention.
[0036] At step 202, the gate region 114 may be functionalized with a bio-receptive layer.
[0037] At step 204, the sample containing the target biomolecules may be introduced.
[0038] At step 206, the changes in the channel current may detected due to the biomolecular interactions.
[0039] At step 208, the measured signal may be analyzed to determine the presence of the concentration of the target biomolecules.
[0040] While the invention has been described in connection with what is presently considered to be the most practical and various embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
[0041] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements within substantial differences from the literal languages of the claims. , Claims:CLAIMS
I/We Claim:
1. A biosensor (100) for detecting biomolecules, characterized in that the biosensor (100) comprising:
a Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer (102) adapted to enhance a spontaneous polarization and a charge accumulation at a heterointerface, wherein the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer (102) is deposited on an Aluminium Gallium Nitride (AlGaN) layer (104);
a graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) (106) adapted to confine a Two-Dimensional Electron Gas (2DEG) and stabilize threshold voltage shifts, wherein the graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) (106) is sandwiched between a Gallium Nitride (GaN) channel (108) and an Iron (Fe) doped Gallium Nitride (GaN) buffer layer (110);
a Silicon Carbide (SiC) substrate (112a-112b) adapted to sandwich the biosensor (100), wherein the sandwiching of the biosensor (100) is adapted to improve a thermal dissipation and stability; and
a functionalized gate region (114) adapted to enable a real-time detection of biomolecular interactions through modulation of channel current, wherein the gate region (114) is etched on the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer (102).
2. The biosensor (100) of claim 1, wherein the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer (102) is adapted to charge density at the heterointerface, improving a sensitivity to the biomolecules.
3. The biosensor (100) of claim 1, wherein the graded-Aluminium Gallium Nitride back-barrier (g-AlGaN-BB) (106) is adapted to Short-Channel Effects (SCEs) and prevents charge migration into the Iron (Fe) doped Gallium Nitride (GaN) buffer layer (110).
4. The biosensor (100) of claim 1, wherein the Silicon Carbide (SiC) substrate (112a-112b) is adapted to enhance thermal conductivity, ensuring stable operation across varying environmental conditions.
5. The biosensor (100) of claim 1, wherein the Silicon Carbide (SiC) substrate (112a-112b) is fabricated using Metal-Organic Chemical Vapor Deposition (MOCVD) to enable scalable and cost-effective manufacturing.
6. The biosensor (100) of claim 1, wherein the gate region (114) comprises a bio-receptive layer that selectively binds the target biomolecules, altering a local charge environment and modulating the channel current.
7. The biosensor (100) of claim 1, wherein the gate region (114) is adapted to initiate a biomolecular binding event results in a threshold voltage shift proportional to a concentration of the target biomolecules.
8. The biosensor (100) of claim 1, wherein a sensitivity of the biomolecule detection is enhanced by optimizing a thickness and composition of the Scandium-alloyed Aluminium Nitride (ScAIN) barrier layer (102).
9. The biosensor (100) of claim 1, wherein the biosensor (100) is a High-Electron-Mobility Transistor (HEMT)-based organic sensor.
10. A method (200) of detecting biomolecules using a biosensor (100), the method (200) is characterized by steps of:
functionalizing a gate region (114) with a bio-receptive layer;
introducing a sample containing the target biomolecules;
detecting changes in channel current due to biomolecular interactions; and
analysing measured signal, due to the changes in the channel current, to determine a presence and a concentration of the target biomolecules.
Date: March 13, 2025
Place: Noida

Nainsi Rastogi
Patent Agent (IN/PA-2372)
Agent for the Applicant