N–Si phases

8 phases (tier A 1, tier C 2, liquid 2, gas 2, needs_review 1); 7 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: interactive registry · full JSON · N–Si system page · Markdown · field reference

Phases of the N–Si system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
DIAMOND_A4 phase:n-si:a4-diamond	C (diamond) · A4 · cF8 · Fd-3m (227)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–1687 K, x(N) 0–0	3	3
GAS phase:n-si:gas	gas	gas	stable in 3 of 3 calculated diagram(s): 300.67–2500 K, x(N) 0.99643–1	4	3
ION phase:n-si:ion	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1687–1974.95 K, x(N) 0–0.46	0	1
LIQUID phase:n-si:liquid	liquid	liquid	stable in 3 of 3 calculated diagram(s): 1686.94–2500 K, x(N) 0–0.00388	8	3
N2GAS phase:n-si:n2gas	gas	gas	stable in 3 of 3 calculated diagram(s): 300–1725 K, x(N) 1–1	0	3
SI3N4 phase:n-si:si3n4		needs_review	stable in 2 of 2 calculated diagram(s): 300–2153.21 K, x(N) 0.57143–0.57143	9	2
SI3N4_A phase:n-si:si3n4-a	Si3N4-alpha · hP28 · P31c (159)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	not stable in 1 calculated diagram(s)	0	1
SI3N4_B phase:n-si:si3n4-b	Si3N4-beta · hP14 · R-3c (167)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–2213.83 K, x(N) 0.57143–0.57143	0	1

DIAMOND_A4 (N–Si)

Id: phase:n-si:a4-diamond; status assigned
Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type st:a4-c-diamond-cf8; tier A: standard phase name; confidence high
Stoichiometry: Si 1.0000
Stability: stable in 3 of 3 calculated diagram(s): 300–1687 K, x(N) 0–0
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:n-si:a4-diamond, corpus:phase:n-si:diamond-a4
paper: paper:10.1016/j.calphad.2003.12.005:diamond_Si
tdb: tdb:SiN-03Ma-LB.tdb:DIAMOND_A4, tdb:SiN-18Sri.tdb:DIAMOND_A4, tdb:SiN-92Hil.tdb:DIAMOND_A4

TDB models of DIAMOND_A4 (3): PHASE and CONSTITUENT statements as written

SiN-03Ma-LB.tdb: DIAMOND_A4, type code %, sha256 82df19923aefac84…

36: PHASE DIAMOND_A4 % 1 1 !
37: CONST DIAMOND_A4 : SI : !

SiN-18Sri.tdb: DIAMOND_A4, type code %, sha256 05fdadd753872c55…

43: PHASE DIAMOND_A4 % 1 1 !
44: CONST DIAMOND_A4 : SI : !

SiN-92Hil.tdb: DIAMOND_A4, type code %, sha256 f49087962923feaa…

45: PHASE DIAMOND_A4 % 1 1 !
46: CONST DIAMOND_A4 : SI : !

Example references (5 of 5; assessments first):

doi:10.1016/j.calphad.2003.12.005 Xiaoyan Ma, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Si–N system, Calphad 27, 383-388 (2003).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase
doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase
doi:10.1063/1.1735180 W. Kaiser, C. D. Thurmond, Nitrogen in Silicon, Journal of Applied Physics 30, 427-431 (1959).
cited as the source of values for this phase
doi:10.1149/1.2403610 Y. Yatsurugi, N. Akiyama, Y. Endo, T. Nozaki, Concentration, Solubility, and Equilibrium Distribution Coefficient of Nitrogen and Oxygen in Semiconductor Silicon, J. Electrochem. Soc. 120, 975 (1973).
cited as the source of values for this phase

GAS (N–Si)

Id: phase:n-si:gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300.67–2500 K, x(N) 0.99643–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:n-si:gas
paper: paper:10.1016/j.calphad.2003.12.005:gas
tdb: tdb:SiN-03Ma-LB.tdb:GAS, tdb:SiN-18Sri.tdb:GAS, tdb:SiN-92Hil.tdb:GAS

TDB models of GAS (3): PHASE and CONSTITUENT statements as written

SiN-03Ma-LB.tdb: GAS, type code %, sha256 82df19923aefac84…

44: PHASE GAS:G % 1 1 !
45: CONST GAS:G : N N2 N3 SI SI2 SI3 SIN SI2N : !

SiN-18Sri.tdb: GAS, type code %, sha256 05fdadd753872c55…

56: PHASE GAS:G % 1 1 !
57: CONST GAS:G : N N2 N3 SI SI2 SI3 SIN SI2N : !

SiN-92Hil.tdb: GAS, type code %, sha256 f49087962923feaa…

53: PHASE GAS:G % 1 1 !
54: CONST GAS:G : N N2 N3 SI SI2 SI3 SIN SI2N : !

Example references (5 of 5; assessments first):

doi:10.1016/j.calphad.2003.12.005 Xiaoyan Ma, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Si–N system, Calphad 27, 383-388 (2003).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase
doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase
doi:10.1007/bf00542737 P. Dörner, L. J. Gauckler, H. Krieg, H. L. Lukas, G. Petzow, J. Weiss, Calculation of heterogeneous phase equilibria in the SiAlON system, J Mater Sci 16, 935-943 (1981).
cited as the source of values for this phase
doi:10.1063/1.1735180 W. Kaiser, C. D. Thurmond, Nitrogen in Silicon, Journal of Applied Physics 30, 427-431 (1959).
cited as the source of values for this phase

ION (N–Si)

Id: phase:n-si:ion; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1687–1974.95 K, x(N) 0–0.46
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:n-si:ion
tdb: tdb:SiN-92Hil.tdb:ION

TDB models of ION (1): PHASE and CONSTITUENT statements as written

SiN-92Hil.tdb: ION, type code %, sha256 f49087962923feaa…

40: PHASE ION:Y % 2 1 1 !
41: CONST ION:Y : SI+4 : N-3 SIN1_3 VA : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase

LIQUID (N–Si)

Id: phase:n-si:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 1686.94–2500 K, x(N) 0–0.00388
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:n-si:liquid
paper: paper:10.1016/j.calphad.2003.12.005:L, paper:10.1016/j.calphad.2003.12.005:liquid
tdb: tdb:SiN-03Ma-LB.tdb:LIQUID, tdb:SiN-18Sri.tdb:LIQUID, tdb:SiN-92Hil.tdb:LIQUID

TDB models of LIQUID (3): PHASE and CONSTITUENT statements as written

SiN-03Ma-LB.tdb: LIQUID, type code %, sha256 82df19923aefac84…

31: PHASE LIQUID:L % 1 1 !
32: CONST LIQUID:L : N SI : !

SiN-18Sri.tdb: LIQUID, type code %, sha256 05fdadd753872c55…

38: PHASE LIQUID:L % 1 1 !
39: CONST LIQUID:L : N SI : !

SiN-92Hil.tdb: LIQUID, type code %, sha256 f49087962923feaa…

37: PHASE LIQUID:L % 1 1 !
38: CONST LIQUID:L : N SI : !

Example references (6 of 6; assessments first):

doi:10.1016/j.calphad.2003.12.005 Xiaoyan Ma, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Si–N system, Calphad 27, 383-388 (2003).
assessment that models this phase; reports values for this phase
doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase
doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase
doi:10.1063/1.1735180 W. Kaiser, C. D. Thurmond, Nitrogen in Silicon, Journal of Applied Physics 30, 427-431 (1959).
cited as the source of values for this phase
doi:10.1149/1.2403610 Y. Yatsurugi, N. Akiyama, Y. Endo, T. Nozaki, Concentration, Solubility, and Equilibrium Distribution Coefficient of Nitrogen and Oxygen in Semiconductor Silicon, J. Electrochem. Soc. 120, 975 (1973).
cited as the source of values for this phase
doi:10.1007/bf00542737 P. Dörner, L. J. Gauckler, H. Krieg, H. L. Lukas, G. Petzow, J. Weiss, Calculation of heterogeneous phase equilibria in the SiAlON system, J Mater Sci 16, 935-943 (1981).
cited as the source of values for this phase

N2GAS (N–Si)

Id: phase:n-si:n2gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300–1725 K, x(N) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:n-si:n2gas
tdb: tdb:SiN-03Ma-LB.tdb:N2GAS, tdb:SiN-18Sri.tdb:N2GAS, tdb:SiN-92Hil.tdb:N2GAS

TDB models of N2GAS (3): PHASE and CONSTITUENT statements as written

SiN-03Ma-LB.tdb: N2GAS, type code %, sha256 82df19923aefac84…

47: PHASE N2GAS % 1 1 !
48: CONST N2GAS : N2 : !

SiN-18Sri.tdb: N2GAS, type code %, sha256 05fdadd753872c55…

59: PHASE N2GAS % 1 1 !
60: CONST N2GAS : N2 : !

SiN-92Hil.tdb: N2GAS, type code %, sha256 f49087962923feaa…

56: PHASE N2GAS % 1 1 !
57: CONST N2GAS : N2 : !

Example references (3 of 3; assessments first):

doi:10.1016/j.calphad.2003.12.005 Xiaoyan Ma, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Si–N system, Calphad 27, 383-388 (2003).
assessment that models this phase
doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase
doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase

SI3N4 (N–Si)

Id: phase:n-si:si3n4; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition; sgte_mmc2_rows_disagree
Candidate (dft_mp): P6_3/m (176) — on-hull MP Si3N4 at x(SI)=0.4286
Candidate (dft_oqmd): P63/m (176) — on-hull OQMD N4 Si3 at x(SI)=0.4286
Candidate (literature_printed): Si3N4-alpha · hP28 — printed with a label mapped to this phase
Candidate (sgte_mmc2): Si3N4-alpha · hP28 · P31c (159) — Hallstedt 2025 mmc2 row for SI3N4: Si3N4
Candidate (sgte_mmc2): Si3N4-beta · hP14 · R-3c (167) — Hallstedt 2025 mmc2 row for SI3N4: Si3N4
Candidate (tdb_comment): Si3N4; alpha: · hP28 · p31c — SiN-03Ma-LB.tdb: 'Prototype Si3N4; alpha: (hP28, p31c), beta: (hP14, P6_3)'
Candidate (tdb_comment): Si3N4; alpha: · hP28 · p31c — SiN-92Hil.tdb: 'Prototype Si3N4; alpha: (hP28, p31c), beta: (hP14, P6_3)'
Stoichiometry: N 0.5714, Si 0.4286
Stability: stable in 2 of 2 calculated diagram(s): 300–2153.21 K, x(N) 0.57143–0.57143
Literature: 9 values (9 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:n-si:si3n4
paper: paper:10.1016/j.calphad.2003.12.005:Si3N4
tdb: tdb:SiN-03Ma-LB.tdb:SI3N4, tdb:SiN-92Hil.tdb:SI3N4

TDB models of SI3N4 (2): PHASE and CONSTITUENT statements as written

SiN-03Ma-LB.tdb: SI3N4, type code %, sha256 82df19923aefac84…

41: PHASE SI3N4 % 2 3 4 !
42: CONST SI3N4 : SI : N : !

SiN-92Hil.tdb: SI3N4, type code %, sha256 f49087962923feaa…

50: PHASE SI3N4 % 2 3 4 !
51: CONST SI3N4 : SI : N : !

Example references (5 of 5; assessments first):

doi:10.1016/j.calphad.2003.12.005 Xiaoyan Ma, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Si–N system, Calphad 27, 383-388 (2003).
assessment that models this phase; reports values for this phase
doi:10.1515/ijmr-1992-830902 M. Hillert, S. Jonsson, B. Sundman, Z. Metallkd., 83, 648-54(1992).
assessment that models this phase
doi:10.1063/1.1735180 W. Kaiser, C. D. Thurmond, Nitrogen in Silicon, Journal of Applied Physics 30, 427-431 (1959).
cited as the source of values for this phase
doi:10.1007/bf00542737 P. Dörner, L. J. Gauckler, H. Krieg, H. L. Lukas, G. Petzow, J. Weiss, Calculation of heterogeneous phase equilibria in the SiAlON system, J Mater Sci 16, 935-943 (1981).
cited as the source of values for this phase
doi:10.1149/1.2403610 Y. Yatsurugi, N. Akiyama, Y. Endo, T. Nozaki, Concentration, Solubility, and Equilibrium Distribution Coefficient of Nitrogen and Oxygen in Semiconductor Silicon, J. Electrochem. Soc. 120, 975 (1973).
cited as the source of values for this phase

SI3N4_A (N–Si)

Id: phase:n-si:si3n4-a; status assigned
Structure: Si3N4-alpha · hP28 · P31c (159); type st:si3n4-alpha-hp28; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (name_has_descriptive_tokens:A, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: N 0.5714, Si 0.4286
Stability: not stable in 1 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:n-si:si3n4-a
tdb: tdb:SiN-18Sri.tdb:SI3N4_A

TDB models of SI3N4_A (1): PHASE and CONSTITUENT statements as written

SiN-18Sri.tdb: SI3N4_A, type code %, sha256 05fdadd753872c55…

48: PHASE SI3N4_A % 2 3 4 !
49: CONST SI3N4_A : SI : N : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase

SI3N4_B (N–Si)

Id: phase:n-si:si3n4-b; status assigned
Structure: Si3N4-beta · hP14 · R-3c (167); type st:si3n4-beta-hp14; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (name_has_descriptive_tokens:B, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: N 0.5714, Si 0.4286
Stability: stable in 1 of 1 calculated diagram(s): 300–2213.83 K, x(N) 0.57143–0.57143
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:n-si:si3n4-b
tdb: tdb:SiN-18Sri.tdb:SI3N4_B

TDB models of SI3N4_B (1): PHASE and CONSTITUENT statements as written

SiN-18Sri.tdb: SI3N4_B, type code %, sha256 05fdadd753872c55…

53: PHASE SI3N4_B % 2 3 4 !
54: CONST SI3N4_B : SI : N : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.06.004 S. Sridar, R. Kumar, K. C. Hari Kumar, Calphad, 62, 148-53(2018).
assessment that models this phase

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Registry: phase registry of binary systems (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735970
R. Arróyave, J. Saal, D. Shin, ORCHID data: umbrella record of the ORCHID datasets (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23736065

Also cite B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, https://doi.org/10.1016/j.calphad.2025.102833 (CC BY 4.0), and the original assessment named in each file; A. Jain et al., The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002, https://doi.org/10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501, https://doi.org/10.1007/s11837-013-0755-4 and S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010, https://doi.org/10.1038/npjcompumats.2015.10 (CC BY 4.0); the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work). Version 1, machine-extracted: values were read by language-model readers constrained to quote their source and checked automatically, and the release was then audited on the printed pages by adversarial audits, an independent second review of fit-facing records and a preliminary human review of a frozen sample. Flags such as accepted and ESPEI-ready record screening results, not certification; known issues are listed in the release notes.

@misc{orchid_phase_registry_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Registry: phase registry of binary systems}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735970},
  url       = {https://doi.org/10.5281/zenodo.23735970},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_data_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID data: umbrella record of the ORCHID datasets}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23736065},
  url       = {https://doi.org/10.5281/zenodo.23736065},
  note      = {Version 1, machine-extracted}
}