Patent: 6,307,731
Summary for Patent: 6,307,731
| Title: | Dielectric capacitor and memory and method of manufacturing the same | ||||||||||||||||||||||||||||||||||||||||||
| Abstract: | Provided are a dielectric capacitor, in which micorfabrication is easily performed, a memory and a method of manufacturing the dielectric capacitor and the memory. A bottom electrode, a dielectric film and a top electrode are sequentially provided on a substrate portion. The bottom electrode comprises an adhesive layer including IrHf, a precious metal layer including Ir, an oxygen inclusion layer including IrHfO and, a precious metal layer including Ir in sequence on the substrate portion. The top electrode comprises, a precious metal layer including Ir and an oxygen inclusion layer including IrHfO in sequence on the dielectric film. Since platinum is not used for the top electrode and the bottom electrode, microfabrication thereof is facilitated Further, the top electrode is deposited before crystallizing or crystal growing the dielectric film, and thereby the top electrode and the bottom electrode can be processed by etching. As a result, etching can be performed on its smooth surface, allowing easier microfabrication. | ||||||||||||||||||||||||||||||||||||||||||
| Inventor(s): | Katori; Kenji (Kanagawa, JP) | ||||||||||||||||||||||||||||||||||||||||||
| Assignee: | Sony Corporation (Tokyo, JP) | ||||||||||||||||||||||||||||||||||||||||||
| Application Number: | 09/584,140 | ||||||||||||||||||||||||||||||||||||||||||
| Patent Claims: | see list of patent claims | ||||||||||||||||||||||||||||||||||||||||||
| Patent landscape, scope, and claims summary: | US Patent 6,307,731 Landscape and Claim-Strength AnalysisUS Patent 6,307,731 claims a dielectric capacitor and memory architecture where the key novelty sits in the electrode microstructure: an oxygen inclusion material in an electrode (and optionally separate precious-metal and adhesive layers), paired with a specific bismuth-layered ferroelectric dielectric composition (Bi-based layer-structured oxide of the type Bi_x(Sr,Ca,Ba)_y(Ta,Nb)_2O_{9+z}). The claims also define manufacturing steps using oxygen annealing, inert annealing, and sometimes reduction and hydrogen annealing. What matters for enforceability and freedom-to-operate (FTO) is that the independent claim elements are highly specific in chemistry, layer placement, and anneal/reduction sequences, which narrows literal coverage but increases the chance that close substitutes exist. What are the core claim elements and what do they actually require?Independent claim 1: dielectric capacitor with oxygen-inclusion electrode chemistryClaim 1 requires, in combination:
This is not “oxygen-containing precious metal electrodes” in general. It is a tight compositional spec with multiple element-family restrictions and an explicit atomic-percent equation. Claim 2: optional precious-metal layer under/over the oxygen-inclusion layerClaim 2 requires the second electrode further comprises a second electrode precious metal layer provided between the oxygen inclusion layer and the dielectric film. So even if someone adopts the oxygen inclusion chemistry in the electrode stack, they may still avoid some claims by altering layer order or omitting the intermediate precious-metal layer. Claims 3-7: first electrode oxygen inclusion and adhesive stackClaim 3 requires the first electrode contains an oxygen inclusion layer with composition formula:
Claim 4 then adds a layer stack:
Claim 5 specifies adhesive chemistry as:
Claim 6 further restricts adhesive layer ingredients to include at least one of:
Claim 7 adds an optional additional precious metal layer:
Net effect: the electrode stack claims are layer-order dependent and chemistry dependent, so an FTO attack can target either the inclusion chemistry (atom % and element selection) or the stack layering. Claims 8-10: dielectric film is a Bi-based layer-structured oxideClaim 8 requires the dielectric film is a ferroelectric including layer structure oxide containing bismuth (Bi). Claim 9 gives a more concrete composition formula:
Claim 10 narrows to the specific expression:
This creates a two-part tight coupling:
If a competitor uses a different ferroelectric (even another Bi-based one) or a different layered composition outside the defined range, claim 9/10 may not read. Claims 11-12: memory adds transistor couplingClaim 11 claims a memory with the same dielectric capacitor structure as claim 1. Claim 12 adds:
This is architecture-level; design-around can alter interconnect scheme so the transistor is not connected through the claimed plug-layer relationship. How do dependent claims expand or narrow scope?Layer stacking is a practical design-around leverAcross claims 2, 4, 7, the patent forces particular placements:
A competitor can often reduce risk of literal infringement by changing:
Adhesive claim is constrained chemicallyClaims 5-6 define adhesive as a precious + transition metal alloy with narrow precious-metal dominance plus a limited element list (including Ti or Zr/Hf/Ta/Nb/Cr/Mo/W). An alternative adhesion chemistry can be used to avoid those dependent claim hooks. Manufacturing claims add process sequence constraintsClaims 13-21, and 22-25 incorporate process constraints:
Process claims can be easier to avoid by changing thermal budget, atmosphere chemistry, annealing order, or whether hydrogen anneal steps exist. What is the patent’s likely novelty thesis and how does that affect validity?The claims suggest the inventors’ thesis is that electrode oxygen incorporation (oxygen inclusion materials composed of precious + transition metals with defined atomic ranges) and particular anneal/reduction schemes:
Under standard US patent scrutiny, novelty usually rides on at least one of:
Validity risk points:
But the claims are drafted so that each dependent hook narrows chemical and process scope; that drafting strategy can preserve some enforceability even if portions are disclosed in prior art. How strong is the infringement case if a competitor uses a similar product?Literal infringement: chemical and stack matching are gating factorsA claim 1 match requires all of:
Most real products will miss at least one gating element:
Infringement on process claims is narrowerProcess claims (13-21, 22-25) require:
If a competitor uses:
Freedom-to-operate (FTO) focus map: where to probe first1) Oxygen inclusion electrode compositionTarget for non-infringement:
If the competitor’s composition falls outside these windows, claim 1 and claim 3-4-5 paths weaken. 2) Layer orderProbe whether:
3) Adhesive alloyProbe:
4) Ferroelectric compositionIf the product uses the same layered Bi system but outside:
Claim scope summary in a structured matrix
How does this patent fit into the broader US patent landscape for ferroelectric memories?At a strategic level, the landscape around ferroelectric capacitor memories typically clusters into:
US 6,307,731’s claims emphasize the interface engineering through the oxygen inclusion electrode layers plus specific processing atmospheres and sequences. This is consistent with how prior art can cover:
For enforcement, this kind of claim set usually narrows into:
For investment or R&D planning, the patent functions as a “checklist” constraint: verify if any targeted memory stack uses oxygen inclusion precious/transition metal mixtures with atomic-percent windows, and whether deposition and anneal sequences match. Key Takeaways
FAQs1) What is the single most important novelty claim element? 2) Does the patent cover any ferroelectric dielectric? 3) How can a competitor reduce infringement risk quickly? 4) Are the process claims broad enough to capture all manufacturing variations? 5) Is the memory claim broader than the capacitor claim? References (APA)[1] United States Patent 6,307,731. (n.d.). Dielectric capacitor and method for manufacturing the same; memory including the dielectric capacitor. U.S. Patent and Trademark Office. More… ↓ |
Details for Patent 6,307,731
| Applicant | Tradename | Biologic Ingredient | Dosage Form | BLA | Approval Date | Patent No. | Expiredate |
|---|---|---|---|---|---|---|---|
| Pharmalucence Inc | MICROLITE | radiolabeled albumin technetium tc-99m albumin colloid kit | 018263 | March 25, 1983 | 6,307,731 | 2020-05-31 | |
| >Applicant | >Tradename | >Biologic Ingredient | >Dosage Form | >BLA | >Approval Date | >Patent No. | >Expiredate |
